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CVE-2026-128991 xschem 2.9.9 through 3.4.7 Out-of-Bounds Read via read_xschem_file() Embedded-Symbol Record

5.8 medium

Medium (5.8) in stefan schippers xschem.

On this page
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.

Severity

CVSS 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

CVSS 3.1

5.3 medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H
CISA's assessment (SSVC)
Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-125 Out-of-bounds Read
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

  • stefan schippers:xschem

Versions

From the CNA's record in the CVE List.

ProductAffected
Stefan Schippers xschemfrom 2.9.9 through 3.4.7

Attack patterns (CAPEC)

  • CAPEC-540 Overread Buffers Likelihood: Low · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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