{"id":"CVE-2026-66338","aliases":["AZL-94095","CLSA-2026-1787732034","CLSA-2026-1787732250","CLSA-2026-1787751026","CLSA-2026-1787783675","DEBIAN-CVE-2026-66338","EUVD-2026-48752","GHSA-8wm8-3499-x4v9","OESA-2026-3690","OESA-2026-3691","OESA-2026-3692","OESA-2026-3693","OESA-2026-4391","UBUNTU-CVE-2026-66338"],"status":"published","title":"Libsoup: libsoup: http request smuggling via permissive chunk-size parsing in soup_body_input_stream_read_chunked()","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","severity":{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00291,"percentile":0.21928,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-444"],"published":"2026-07-24T23:01:20Z","modified":"2026-11-10T02:51:07Z","fixes":[{"ecosystem":"TuxCare:RHEL:7","package":"libsoup","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:RHEL:7","package":"libsoup-devel","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:OracleLinux:7","package":"libsoup","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:OracleLinux:7","package":"libsoup-devel","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:CentOS:7","package":"libsoup","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:CentOS:7","package":"libsoup-devel","fixed_in":["2.62.2-2.0.11.el7.tuxcare.els3"],"sources":["osv"]},{"ecosystem":"TuxCare:AlmaLinux:9.6","package":"libsoup","fixed_in":["2.72.0-10.el9_6.3.tuxcare.els9"],"sources":["osv"]},{"ecosystem":"TuxCare:AlmaLinux:9.6","package":"libsoup-devel","fixed_in":["2.72.0-10.el9_6.3.tuxcare.els9"],"sources":["osv"]},{"ecosystem":"TuxCare:AlmaLinux:9.6","package":"libsoup-doc","fixed_in":["2.72.0-10.el9_6.3.tuxcare.els9"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Azure 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hat","product":"red hat enterprise linux 10"},{"vendor":"red hat","product":"red hat enterprise linux 6"},{"vendor":"red hat","product":"red hat enterprise linux 7"},{"vendor":"red hat","product":"red hat enterprise linux 8"},{"vendor":"red hat","product":"red hat enterprise linux 9"},{"vendor":"redhat","product":"enterprise_linux"}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-66338","tags":["vdb-entry","x_refsource_REDHAT","Vendor Advisory","report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2506950","tags":["issue-tracking","x_refsource_REDHAT","Exploit","Issue Tracking","Vendor Advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66338","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-8wm8-3499-x4v9"},{"url":"https://errata.tuxcare.com/els_os/rhel7els/CLSA-2026-1787732034.html","tags":["advisory"]},{"url":"https://errata.tuxcare.com/els_os/oraclelinux7els/CLSA-2026-1787732250.html","tags":["advisory"]},{"url":"https://errata.tuxcare.com/els_os/centos7els/CLSA-2026-1787751026.html","tags":["advisory"]},{"url":"https://errata.tuxcare.com/els_os/tuxcare9.6esu/CLSA-2026-1787783675.html","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-66338","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3690","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12548","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12549","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77014","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77680","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3691","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3692","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-15711","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3693","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4391","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12547","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66337","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-66338","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-66338","tags":["report"]},{"url":"https://gitlab.gnome.org/GNOME/libsoup/-/work_items/533","tags":["report"]},{"url":"https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/563","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-66338","title":"Libsoup: libsoup: http request smuggling via permissive chunk-size parsing in soup_body_input_stream_read_chunked()","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:01:20.503Z","modified":"2026-11-06T19:27:20.998Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-444"],"updated_at":"2026-11-06T20:30:05.028126Z"}],"euvd":[{"id":"EUVD-2026-48752","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:01:20Z","modified":"2026-11-06T19:27:20Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-06T20:06:05.048214Z"}],"ghsa":[{"id":"GHSA-8wm8-3499-x4v9","title":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing...","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-25T00:31:48Z","modified":"2026-07-25T00:31:53Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-444"],"updated_at":"2026-11-02T15:09:49.369416Z"}],"nvd":[{"id":"CVE-2026-66338","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:16:52.04Z","modified":"2026-11-06T20:17:24.567Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high","assessor":"primary"}],"cwes":["CWE-444"],"updated_at":"2026-11-06T22:02:12.917468Z"}],"osv":[{"id":"DEBIAN-CVE-2026-66338","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:16:52.04Z","modified":"2026-11-07T09:47:33.044274254Z","cvss":[{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high"}],"updated_at":"2026-11-07T10:14:39.995311Z"},{"id":"OESA-2026-3690","title":"libsoup security update","description":"libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.\r\n\r\nSecurity Fix(es):\n\nA heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents.(CVE-2026-12548)\n\nThe fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.(CVE-2026-12549)\n\nA flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.(CVE-2026-66338)\n\nA flaw was found in libsoup\u0026apos;s SoupServer HTTP Range header processing. The sort_ranges() comparator in soup-message-headers.c truncates a 64-bit subtraction result to 32-bit int, flipping the sign for range offsets differing by more than INT_MAX. This causes silent omission of requested byte ranges from HTTP 206 Partial Content responses on resources larger than approximately 2 GB.(CVE-2026-77014)\n\nAn algorithmic complexity flaw exists in libsoup\u0026apos;s HTTP Range header processing that persists after the CVE-2025-32907 fix. CVE-2025-32907 addressed memory amplification when a client repeated the same range many times in a single Range header. Commit 9bb92f7a corrected merge correctness in soup_message_headers_get_ranges_internal() in libsoup/soup-message-headers.c, but the coalescing loop still removes merged ranges using g_array_remove_index() for each coalesced element. Because GArray is contiguous, each mid-array removal performs an O(N) memmove. When many identical satisfiable ranges are supplied (for example bytes=0-0 repeated thousands of times), the loop performs O(N²) work coalescing them into a single range. The vulnerable path is reachable server-side from handle_partial_get() in libsoup/server/http1/soup-server-message-io-http1.c when a SoupServer handler returns HTTP 200 with a non-empty body. No authentication is required. The number of ranges is bounded only by the maximum request header size (~100 KiB), allowing roughly 25,000 ranges per request. This is a CPU exhaustion / availability issue only. No memory corruption or information disclosure occurs.(CVE-2026-77680)","status":"published","published":"2026-09-05T15:03:58Z","modified":"2026-09-05T15:16:38.127170704Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:47.217107Z"},{"id":"OESA-2026-3691","title":"libsoup security update","description":"libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.\r\n\r\nSecurity Fix(es):\n\nA heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents.(CVE-2026-12548)\n\nThe fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.(CVE-2026-12549)\n\nA flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.(CVE-2026-66338)\n\nA flaw was found in libsoup\u0026apos;s SoupServer HTTP Range header processing. The sort_ranges() comparator in soup-message-headers.c truncates a 64-bit subtraction result to 32-bit int, flipping the sign for range offsets differing by more than INT_MAX. This causes silent omission of requested byte ranges from HTTP 206 Partial Content responses on resources larger than approximately 2 GB.(CVE-2026-77014)\n\nAn algorithmic complexity flaw exists in libsoup\u0026apos;s HTTP Range header processing that persists after the CVE-2025-32907 fix. CVE-2025-32907 addressed memory amplification when a client repeated the same range many times in a single Range header. Commit 9bb92f7a corrected merge correctness in soup_message_headers_get_ranges_internal() in libsoup/soup-message-headers.c, but the coalescing loop still removes merged ranges using g_array_remove_index() for each coalesced element. Because GArray is contiguous, each mid-array removal performs an O(N) memmove. When many identical satisfiable ranges are supplied (for example bytes=0-0 repeated thousands of times), the loop performs O(N²) work coalescing them into a single range. The vulnerable path is reachable server-side from handle_partial_get() in libsoup/server/http1/soup-server-message-io-http1.c when a SoupServer handler returns HTTP 200 with a non-empty body. No authentication is required. The number of ranges is bounded only by the maximum request header size (~100 KiB), allowing roughly 25,000 ranges per request. This is a CPU exhaustion / availability issue only. No memory corruption or information disclosure occurs.(CVE-2026-77680)","status":"published","published":"2026-09-05T15:03:59Z","modified":"2026-09-05T15:16:38.128294417Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:47.217107Z"},{"id":"OESA-2026-3692","title":"libsoup security update","description":"libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.\r\n\r\nSecurity Fix(es):\n\nA heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents.(CVE-2026-12548)\n\nThe fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.(CVE-2026-12549)\n\nA vulnerability was found in libsoup\u0026apos;s WebSocket frame parsing implementation. The library fails to validate length rules specified in RFC 6455 §5.5, which mandates that all WebSocket control frames (e.g., PING, PONG, CLOSE) contain a payload of 125 bytes or less. A remote, unauthenticated attacker can exploit this by sending a non-compliant, oversized control frame. Because the parser handles this protocol violation improperly instead of throwing an immediate connection termination error, it triggers a internal processing crash, resulting in a remote denial of service (DoS) for applications utilizing libsoup WebSockets.(CVE-2026-15711)\n\nA flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.(CVE-2026-66338)\n\nA flaw was found in libsoup\u0026apos;s SoupServer HTTP Range header processing. The sort_ranges() comparator in soup-message-headers.c truncates a 64-bit subtraction result to 32-bit int, flipping the sign for range offsets differing by more than INT_MAX. This causes silent omission of requested byte ranges from HTTP 206 Partial Content responses on resources larger than approximately 2 GB.(CVE-2026-77014)\n\nAn algorithmic complexity flaw exists in libsoup\u0026apos;s HTTP Range header processing that persists after the CVE-2025-32907 fix. CVE-2025-32907 addressed memory amplification when a client repeated the same range many times in a single Range header. Commit 9bb92f7a corrected merge correctness in soup_message_headers_get_ranges_internal() in libsoup/soup-message-headers.c, but the coalescing loop still removes merged ranges using g_array_remove_index() for each coalesced element. Because GArray is contiguous, each mid-array removal performs an O(N) memmove. When many identical satisfiable ranges are supplied (for example bytes=0-0 repeated thousands of times), the loop performs O(N²) work coalescing them into a single range. The vulnerable path is reachable server-side from handle_partial_get() in libsoup/server/http1/soup-server-message-io-http1.c when a SoupServer handler returns HTTP 200 with a non-empty body. No authentication is required. The number of ranges is bounded only by the maximum request header size (~100 KiB), allowing roughly 25,000 ranges per request. This is a CPU exhaustion / availability issue only. No memory corruption or information disclosure occurs.(CVE-2026-77680)","status":"published","published":"2026-09-05T15:03:59Z","modified":"2026-09-05T15:16:37.827333611Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:47.217107Z"},{"id":"OESA-2026-3693","title":"libsoup security update","description":"libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.\r\n\r\nSecurity Fix(es):\n\nA heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents.(CVE-2026-12548)\n\nThe fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.(CVE-2026-12549)\n\nA flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.(CVE-2026-66338)\n\nA flaw was found in libsoup\u0026apos;s SoupServer HTTP Range header processing. The sort_ranges() comparator in soup-message-headers.c truncates a 64-bit subtraction result to 32-bit int, flipping the sign for range offsets differing by more than INT_MAX. This causes silent omission of requested byte ranges from HTTP 206 Partial Content responses on resources larger than approximately 2 GB.(CVE-2026-77014)\n\nAn algorithmic complexity flaw exists in libsoup\u0026apos;s HTTP Range header processing that persists after the CVE-2025-32907 fix. CVE-2025-32907 addressed memory amplification when a client repeated the same range many times in a single Range header. Commit 9bb92f7a corrected merge correctness in soup_message_headers_get_ranges_internal() in libsoup/soup-message-headers.c, but the coalescing loop still removes merged ranges using g_array_remove_index() for each coalesced element. Because GArray is contiguous, each mid-array removal performs an O(N) memmove. When many identical satisfiable ranges are supplied (for example bytes=0-0 repeated thousands of times), the loop performs O(N²) work coalescing them into a single range. The vulnerable path is reachable server-side from handle_partial_get() in libsoup/server/http1/soup-server-message-io-http1.c when a SoupServer handler returns HTTP 200 with a non-empty body. No authentication is required. The number of ranges is bounded only by the maximum request header size (~100 KiB), allowing roughly 25,000 ranges per request. This is a CPU exhaustion / availability issue only. No memory corruption or information disclosure occurs.(CVE-2026-77680)","status":"published","published":"2026-09-05T15:04:00Z","modified":"2026-09-05T15:16:38.134530749Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:47.217107Z"},{"id":"OESA-2026-4391","title":"libsoup security update","description":"libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.\r\n\r\nSecurity Fix(es):\n\nSoupAuthManager caches proxy authentication credentials without scoping them to the proxy authority (host:port). When the proxy configuration changes (e.g., via system settings or WPAD), cached Proxy-Authorization headers from the previous proxy are sent to the new proxy, leaking credentials.(CVE-2026-12547)\n\nA flaw was found in libsoup. An unsigned integer underflow in the soup_filter_input_stream_read_until() function causes a heap buffer over-read when parsing multipart HTTP responses. A malicious HTTP server can exploit this by sending a crafted multipart response, potentially causing the client application to crash or disclose sensitive heap memory.(CVE-2026-66337)\n\nA flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.(CVE-2026-66338)","status":"published","published":"2026-10-16T12:00:06Z","modified":"2026-10-16T12:15:13.689534088Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T15:52:47.981622Z"},{"id":"UBUNTU-CVE-2026-66338","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:16:00Z","modified":"2026-11-10T02:51:07.678067683Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"medium"},{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high"}],"updated_at":"2026-11-10T03:19:55.713577Z"},{"id":"AZL-94095","title":"CVE-2026-66338 affecting package libsoup 3.4.4-18","description":"A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.","status":"published","published":"2026-07-24T23:16:52Z","modified":"2026-11-05T05:40:51Z","updated_at":"2026-11-05T16:41:25.880689Z"},{"id":"CLSA-2026-1787732034","title":"libsoup: Fix of CVE-2026-66338","description":"- CVE-2026-66338: reject chunk-size lines that violate RFC 9112 (leading\n  whitespace, sign prefix, \"0x\" prefix or trailing garbage) in\n  soup_body_input_stream_read_chunked() to prevent HTTP request smuggling","status":"published","published":"2026-08-26T08:14:10Z","modified":"2026-10-26T09:31:58.585317381Z","updated_at":"2026-11-02T15:43:47.591214Z"},{"id":"CLSA-2026-1787732250","title":"libsoup: Fix of CVE-2026-66338","description":"- CVE-2026-66338: reject chunk-size lines that violate RFC 9112 (leading\n  whitespace, sign prefix, \"0x\" prefix or trailing garbage) in\n  soup_body_input_stream_read_chunked() to prevent HTTP request smuggling","status":"published","published":"2026-08-26T08:17:47Z","modified":"2026-10-26T09:31:56.21522107Z","updated_at":"2026-11-02T15:43:47.591214Z"},{"id":"CLSA-2026-1787751026","title":"libsoup: Fix of CVE-2026-66338","description":"- CVE-2026-66338: reject chunk-size lines that violate RFC 9112 (leading\n  whitespace, sign prefix, \"0x\" prefix or trailing garbage) in\n  soup_body_input_stream_read_chunked() to prevent HTTP request smuggling","status":"published","published":"2026-08-27T16:30:08Z","modified":"2026-10-26T09:31:48.757480164Z","updated_at":"2026-11-02T15:43:47.591214Z"},{"id":"CLSA-2026-1787783675","title":"libsoup: Fix of CVE-2026-66338","description":"- CVE-2026-66338: reject chunk sizes that violate RFC 9112 when parsing the\n  chunked request body, preventing an HTTP request smuggling parsing differential","status":"published","published":"2026-08-26T22:35:18Z","modified":"2026-10-26T09:31:31.615304664Z","updated_at":"2026-11-02T15:43:47.591214Z"}]}}