{"id":"JLSEC-2026-1155","summary":"Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in...","details":"Issue summary: A signed integer overflow when sizing the destination\nbuffer for Unicode output in `ASN1_mbstring_ncopy()` can lead to a heap\nbuffer overflow.\n\nImpact summary: A heap buffer overflow may lead to a crash or possibly\nattacker controlled code execution or other undefined behaviour.\n\nIn `ASN1_mbstring_copy()` and `ASN1_mbstring_ncopy()` the destination\nsize for Unicode output is computed in a signed int: by left shift\nof the input character count for BMPSTRING (UTF-16) and\nUNIVERSALSTRING (UTF-32), and by summing per-character byte counts\nfor UTF8STRING. The calculation overflows when the input reaches\naround 2^30 characters. In the worst case (UNIVERSALSTRING at 2^30\ncharacters) the size wraps to zero, `OPENSSL_malloc`(1) is called, and\nthe subsequent character copy writes several gigabytes past the\none-byte allocation.\n\nX.509 certificate processing routes through `ASN1_STRING_set_by_NID()`,\nwhose `DIRSTRING_TYPE` mask excludes UNIVERSALSTRING and whose per-NID\nsize limits cap the input length; no network protocol or\ncertificate-handling path in OpenSSL exercises the overflow.\nTriggering the bug requires an application that calls\n`ASN1_mbstring_copy()` or `ASN1_mbstring_ncopy()` directly, or registers\na custom string type via `ASN1_STRING_TABLE_add()`, with\nattacker-controlled input on the order of half a gigabyte or more.\nFor these reasons this issue was assigned Low severity.\n\nThe FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by\nthis issue, as the affected code is outside the OpenSSL FIPS module\nboundary.","modified":"2026-08-03T19:20:54.828908894Z","published":"2026-08-03T19:08:57.739Z","upstream":["CVE-2026-7383","EUVD-2026-35474","GHSA-w853-v86g-gv7j"],"database_specific":{"license":"CC-BY-4.0","sources":[{"id":"CVE-2026-7383","imported":"2026-08-03T18:18:16.032Z","modified":"2026-07-23T08:10:00.137Z","published":"2026-06-09T17:17:50.337Z","url":"https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-7383","html_url":"https://nvd.nist.gov/vuln/detail/CVE-2026-7383","database_specific":{"status":"Analyzed"}},{"url":"https://api.github.com/advisories/GHSA-w853-v86g-gv7j","html_url":"https://github.com/advisories/GHSA-w853-v86g-gv7j","id":"GHSA-w853-v86g-gv7j","imported":"2026-08-03T18:18:42.875Z","modified":"2026-06-10T09:32:58Z","published":"2026-06-09T18:31:01Z"},{"id":"EUVD-2026-35474","imported":"2026-08-03T18:18:18.363Z","modified":"2026-06-10T07:47:47Z","published":"2026-06-09T16:03:15Z","url":"https://euvdservices.enisa.europa.eu/api/enisaid?id=EUVD-2026-35474","html_url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-35474"}]},"references":[{"type":"WEB","url":"https://github.com/advisories/GHSA-w853-v86g-gv7j"},{"type":"WEB","url":"https://github.com/openssl/openssl/commit/4f8d2bddaa2c8e06f9c33390ee1717059a6e4be6"},{"type":"WEB","url":"https://github.com/openssl/openssl/commit/80c15faaf78042bbb8654a0e234c50c381732f74"},{"type":"WEB","url":"https://github.com/openssl/openssl/commit/bd17511070fb39a67bfa19682affb765e706a974"},{"type":"WEB","url":"https://github.com/openssl/openssl/commit/c332adaced43bcbb85f97410597e951c11ec3083"},{"type":"WEB","url":"https://github.com/openssl/openssl/commit/d32350ae8ef7426718f5aa9e383d4b51398ee255"},{"type":"WEB","url":"https://github.com/openssl/security/commit/4f8d2bddaa2c8e06f9c33390ee1717059a6e4be6"},{"type":"WEB","url":"https://github.com/openssl/security/commit/80c15faaf78042bbb8654a0e234c50c381732f74"},{"type":"WEB","url":"https://github.com/openssl/security/commit/bd17511070fb39a67bfa19682affb765e706a974"},{"type":"WEB","url":"https://github.com/openssl/security/commit/c332adaced43bcbb85f97410597e951c11ec3083"},{"type":"WEB","url":"https://github.com/openssl/security/commit/d32350ae8ef7426718f5aa9e383d4b51398ee255"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-7383"},{"type":"WEB","url":"https://openssl-library.org/news/secadv/20260609.txt"}],"affected":[{"package":{"name":"AppBundler","ecosystem":"Julia","purl":"pkg:julia/AppBundler?uuid=40eb83ae-c93a-480c-8f39-f018b568f472"},"ranges":[{"type":"SEMVER","events":[{"introduced":"1.0.0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2026/JLSEC-2026-1155.json"}},{"package":{"name":"OpenSSL_jll","ecosystem":"Julia","purl":"pkg:julia/OpenSSL_jll?uuid=458c3c95-2e84-50aa-8efc-19380b2a3a95"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.5.7+0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2026/JLSEC-2026-1155.json"}},{"package":{"name":"Openresty_jll","ecosystem":"Julia","purl":"pkg:julia/Openresty_jll?uuid=87da34d4-7b1b-5a94-8376-8cb65bf3132c"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2026/JLSEC-2026-1155.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}