{"id":"CVE-2026-93838","aliases":["EUVD-2026-83282","GHSA-2wcg-j54r-m6wm","openSUSE-SU-2026:11865-1"],"status":"published","title":"SGLang through 0.5.20 Unbounded Memory Allocation via STAGING_REQ chunk_idx","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","severity":{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00652,"percentile":0.51765,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-770"],"published":"2026-09-18T19:06:03Z","modified":"2026-10-28T02:31:09Z","affected":[{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"python-sglang","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.5.20-1.1"}]}],"bundled":5}],"products":[{"vendor":"sgl-project","product":"sglang"}],"references":[{"url":"https://github.com/sgl-project/sglang/issues/39764","tags":["issue-tracking","exploit","report"]},{"url":"https://github.com/sgl-project/sglang","tags":["product","package"]},{"url":"https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common/staging_handler.py#L781","tags":["technical-description","article"]},{"url":"https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common/staging_handler.py#L848-L860","tags":["technical-description","article"]},{"url":"https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common/conn.py#L1636-L1640","tags":["technical-description","article"]},{"url":"https://www.vulncheck.com/advisories/sglang-through-0.5.20-unbounded-memory-allocation-via-staging-req-chunk-idx","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93838","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-2wcg-j54r-m6wm"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93838.json","tags":["advisory"]},{"url":"https://pypi.org/project/sglang","tags":["package"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2026-86793","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-93088","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-93688","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-93838","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-94570","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2026-93838","title":"SGLang through 0.5.20 Unbounded Memory Allocation via STAGING_REQ chunk_idx","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","status":"published","published":"2026-09-18T19:06:03.899Z","modified":"2026-09-24T14:23:13.073Z","cvss":[{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:19:54.122945Z"}],"euvd":[{"id":"EUVD-2026-83282","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","status":"published","published":"2026-09-18T19:06:03Z","modified":"2026-09-24T14:23:13Z","cvss":[{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T17:27:57.035497Z"}],"ghsa":[{"id":"GHSA-2wcg-j54r-m6wm","title":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in...","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","status":"published","published":"2026-09-18T21:32:27Z","modified":"2026-09-18T21:32:42Z","cvss":[{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:12:12.782251Z"}],"nvd":[{"id":"CVE-2026-93838","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","status":"published","published":"2026-09-18T20:17:33.9Z","modified":"2026-09-22T20:43:58.793Z","cvss":[{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:50.043898Z"}],"osv":[{"id":"CVE-2026-93838","title":"SGLang through 0.5.20 Unbounded Memory Allocation via STAGING_REQ chunk_idx","description":"SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.","status":"published","published":"2026-09-18T19:06:03.899Z","modified":"2026-10-28T02:31:09.017364169Z","cvss":[{"version":"4.0","score":8.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:45:20.931171Z"},{"id":"openSUSE-SU-2026:11865-1","title":"python313-sglang-0.5.20-1.1 on GA media","description":"These are all security issues fixed in the python313-sglang-0.5.20-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-09-23T00:00:00Z","modified":"2026-09-24T18:23:14.723429122Z","updated_at":"2026-11-02T16:58:40.245664Z"}]}}