CVE-2026-128991
xschem 2.9.9 through 3.4.7 Out-of-Bounds Read via read_xschem_file() Embedded-Symbol Record
xschem 2.9.9 through 3.4.7 contains an out-of-bounds read vulnerability in read_xschem_file() in src/save.c that mishandles embedded-symbol records lacking a preceding instance. Attackers can supply a crafted schematic beginning with a "[" record, causing xschem to read and dereference memory below the instance array and crash.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| xschem Stefan Schippers stefanschippers/xschem
github |
≥ 2.9.9; ≤ 3.4.7 (affected, custom)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 5.8 medium |
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 5.3 medium |
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H | CNA: VulnCheck |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/StefanSchippers/xschem/commit/e29af39c6133c36bdaf66603fd663231e75517f1CNA: VulnCheck · patch
- https://github.com/StefanSchippers/xschem/blob/3.4.7/src/save.c#L3138-L3141CNA: VulnCheck · technical-description
- https://github.com/StefanSchippers/xschemCNA: VulnCheck · product
- https://www.vulncheck.com/advisories/xschem-2.9.9-through-3.4.7-out-of-bounds-read-via-read-xschem-file-embedded-symbol-recordCNA: VulnCheck · third-party-advisory
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