{"id":"CVE-2026-102820","title":"pageant provides a [PageantStream] type that implements [AsyncRead] and [AsyncWrite] traits and can be used to talk to a running Pageant instance","summary":"pageant provides a [PageantStream] type that implements [AsyncRead] and [AsyncWrite] traits and can be used to talk to a running Pageant instance. Prior to pageant 0.2.3, the Windows pageant crate's pageant/src/wmmessage.rs MemoryMap::re…","severity":"medium","cvss":6.2,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-125","CWE-789"],"vendor":"Eugeny","product":"russh","affected":["russh < 0.63.2","pageant < 0.2.3"],"published":"2026-09-29","updated":"2026-09-30","sourceUpdated":"2026-09-30T21:17:05.797","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-102820","references":[{"url":"https://github.com/Eugeny/russh/commit/5d566989ebabfdebfe6b33243d31765a0812260b","label":"security-advisories@github.com"},{"url":"https://github.com/Eugeny/russh/releases/tag/v0.63.2","label":"security-advisories@github.com"},{"url":"https://github.com/Eugeny/russh/security/advisories/GHSA-g4mp-vgx3-xrvm","label":"security-advisories@github.com"},{"url":"https://github.com/Eugeny/russh/security/advisories/GHSA-g4mp-vgx3-xrvm","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102820.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-102820"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2543500"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-102820"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102820"},{"url":"https://github.com/advisories/GHSA-g4mp-vgx3-xrvm"},{"url":"https://github.com/Eugeny/russh"}],"tags":["nvd","cve.org","exploit-available","csaf","vex","red-hat","ghsa","rust","osv"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-30T20:11:00.619637Z"},"epss":0.00191,"epssPercentile":0.08663,"scores":{"nvd":6.2,"vendor":5.5,"ghsa":6.2,"osv":6.2},"ingestedAt":"2026-09-29T18:42:35.836Z","aliases":["GHSA-g4mp-vgx3-xrvm"],"ecosystem":"rust","patched":["pageant 0.2.3"],"slug":"CVE-2026-102820","body":"## Overview\n\npageant provides a [PageantStream] type that implements [AsyncRead] and [AsyncWrite] traits and can be used to talk to a running Pageant instance. Prior to pageant 0.2.3, the Windows pageant crate's pageant/src/wmmessage.rs MemoryMap::read function trusts a peer-controlled u32 response length supplied through the 8192-byte Pageant shared-memory mapping reached by AgentClient::connect_pageant. A local process that impersonates the Pageant window can make query_pageant_direct allocate up to approximately 4 GiB and copy beyond the mapped view, reliably crashing a russh client and conditionally exposing adjacent committed memory. This issue is fixed in pageant 0.2.3.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Hardened Images · no fix planned: Red Hat Hardened Images · updated 2026-09-29 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102820.json)\n\n## Package advisory (CVE-2026-102820)\n\nAffected packages:\n\n- `pageant <= 0.2.2`\n\nPatched in:\n\n- `pageant 0.2.3`\n\nSource: https://github.com/advisories/GHSA-g4mp-vgx3-xrvm","depth":"twilight","depthScore":46,"depthScoreParts":{"impact":34.1,"likelihood":0,"exploitation":12,"ransomware":0},"changes":[{"seq":214011,"id":"CVE-2026-102820","ts":1790803604040,"field":"exploit_available","old":"false","new":"true"}]}