{"id":"CVE-2021-39517","aliases":["DEBIAN-CVE-2021-39517","EUVD-2021-25874","GHSA-26c8-846h-xfjj","UBUNTU-CVE-2021-39517"],"status":"published","title":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the...","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.00856,"percentile":0.58863,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-476"],"published":"2021-09-20T15:26:48Z","modified":"2026-10-23T18:03:32Z","fixes":[{"ecosystem":"Debian:12","package":"libjpeg","fixed_in":["0.0~git20200925.f145908-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"libjpeg","fixed_in":["0.0~git20200925.f145908-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"libjpeg","fixed_in":["0.0~git20200925.f145908-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"libjpeg","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~git20200925.f145908-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"libjpeg","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~git20200925.f145908-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"libjpeg","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~git20200925.f145908-1"}]}]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"libjpeg6b","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:6b2-2","1:6b2-2ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"libjpeg","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0~git20190821.87636f3b26b4-1","0.0~git20190821.87636f3b26b4-1.1"]}],"products":[{"vendor":"jpeg","product":"libjpeg"}],"references":[{"url":"https://github.com/thorfdbg/libjpeg/issues/33","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Patch","Third Party Advisory","fix"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-39517"},{"url":"https://github.com/advisories/GHSA-26c8-846h-xfjj"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-39517","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-39517","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-39517","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-39517","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T15:26:48Z","modified":"2024-08-04T02:06:42.557Z","updated_at":"2026-11-02T14:33:09.864034Z"}],"euvd":[{"id":"EUVD-2021-25874","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T15:26:48Z","modified":"2024-08-04T02:06:42Z","updated_at":"2026-11-03T03:24:23.166742Z"}],"ghsa":[{"id":"GHSA-26c8-846h-xfjj","title":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the...","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2022-05-24T19:15:11Z","modified":"2023-01-30T05:02:18Z","cwes":["CWE-476"],"updated_at":"2026-11-02T14:46:36.123786Z"}],"nvd":[{"id":"CVE-2021-39517","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T16:15:11.683Z","modified":"2026-06-17T04:03:44.753Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:06:58.933037Z"}],"osv":[{"id":"CVE-2021-39517","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T16:15:11.683Z","modified":"2026-03-14T11:07:15.773342Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:44:20.843843Z"},{"id":"DEBIAN-CVE-2021-39517","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T16:15:11.683Z","modified":"2026-10-23T18:03:32.367427874Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:45:35.521549Z"},{"id":"UBUNTU-CVE-2021-39517","description":"An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::ReconstructUnsampled() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.","status":"published","published":"2021-09-20T16:15:00Z","modified":"2026-04-22T12:59:47.347294Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:54:28.526929Z"}]}}