CVE Explorer
CVE-2026-35199
SymCrypt is the core cryptographic function library currently used by Windows. From 103.5.0 to before 103.11.0, The SymCryptXmssSign function passes a 64-bit leaf count value to a helper function that accepts a 32-bit parameter. For XMSS^MT parameter sets with total tree height >= 32 (which includes standard predefined parameters), this causes silent truncation to zero, resulting in a drastically undersized scratch buffer allocation followed by a heap buffer overflow during signature computation
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"product":"SymCrypt","vendor":"microsoft","versions":[{"status":"affected","version":">= 103.5.0, < 103.11.0"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:7249000ddf37678db942a6661857b7917febf80c047c7caa6e8456a6ef41a6ea · sha256:6cde55a39ab1258f… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:7249000ddf37678db942a6661857b7917febf80c047c7caa6e8456a6ef41a6ea · sha256:6cde55a39ab1258f… · /containers/cna/metrics/0/cvssV3_1
CWE assertions
1 source assertion{"cweId":"CWE-122","description":"CWE-122: Heap-based Buffer Overflow","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:7249000ddf37678db942a6661857b7917febf80c047c7caa6e8456a6ef41a6ea · sha256:6cde55a39ab1258f… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"https://github.com/microsoft/SymCrypt/security/advisories/GHSA-rvj8-8h6x-hjmg","tags":["x_refsource_CONFIRM"],"url":"https://github.com/microsoft/SymCrypt/security/advisories/GHSA-rvj8-8h6x-hjmg"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:7249000ddf37678db942a6661857b7917febf80c047c7caa6e8456a6ef41a6ea · sha256:6cde55a39ab1258f… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.