{"id":"CVE-2026-102820","summary":"pageant: Out-of-bounds read / oversized allocation in `pageant` MemoryMap::read via a malicious Pageant agent (Windows)","details":"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::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.","aliases":["GHSA-g4mp-vgx3-xrvm"],"modified":"2026-09-30T03:47:23.565990463Z","published":"2026-09-29T18:18:43.297Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102820.json","unresolved_ranges":[{"extracted_events":[{"fixed":"0.2.3"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-125","CWE-789"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102820.json"},{"type":"FIX","url":"https://github.com/Eugeny/russh/commit/5d566989ebabfdebfe6b33243d31765a0812260b"},{"type":"WEB","url":"https://github.com/Eugeny/russh/releases/tag/v0.63.2"},{"type":"ADVISORY","url":"https://github.com/Eugeny/russh/security/advisories/GHSA-g4mp-vgx3-xrvm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102820"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eugeny/russh","events":[{"introduced":"0"},{"fixed":"8a51a0dca4f6fbdcc3ce98c627254026b25b3252"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"0.63.2"}],"source":"AFFECTED_FIELD"}}],"versions":["v0.63.1","v0.63.0","v0.63.0-beta.1","v0.62.7","v0.62.6","v0.62.5","v0.62.4","v0.62.3","v0.62.2","v0.62.1","v0.62.0","v0.61.2","v0.61.1","v0.61.0","v0.60.3","v0.60.2","v0.60.1","v0.60.0","v0.59.0","v0.58.0","v0.57.1","v0.57.0","v0.56.0","v0.55.0","v0.54.6","v0.54.5","v0.54.4","v0.54.3","v0.54.2","v0.54.1","v0.54.0","v0.53.0","v0.53.0-beta.1","v0.52.1","v0.52.0","v0.52.0-beta.1","v0.51.1","v0.51.0","v0.51.0-beta.3","v0.51.0-beta.2","v0.51.0-beta.1","v0.50.4","v0.50.3","v0.50.1","v0.50.0","v0.50.0-beta.12","v0.50.0-beta.11","v0.50.0-beta.10","v0.50.0-beta.9","v0.50.0-beta.8","v0.50.0-beta.7","v0.50.0-beta.6","v0.50.0-beta.5","v0.50.0-beta.4","v0.50.0-beta.3","v0.50.0-beta.2","v0.49.0","v0.48.2","v0.48.1","v0.48.0","v0.47.0-beta.4","v0.47.0-beta.3","v0.46.0","v0.45.0","v0.44.0","v0.44.0-beta.4","v0.44.0-beta.3","v0.44.0-beta.1","v0.43.0","v0.43.0-beta.1","v0.42.0","v0.40.2","v0.40.1","v0.40.0","v0.38.0","v0.39.0-beta.1","v0.38.0-beta.1","v0.37.1","v0.37.0","v0.36.1","v0.37.0-beta.1","0.37.0-beta.1","v0.35.0-beta.9","v0.35.0-beta.8","v0.35.0-beta.7","v0.35.0-beta.6","v0.35.0-beta.5","v0.35.0-beta.3","v0.35.0-beta.2","v0.35.0-beta.1","v0.34.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-102820.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}