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Fencer Intel
high 8.1

CVE-2026-75614 json

ASN1SCC: Out-of-bounds write in BitStream_DecodeConstraintWholeNumber (uPER/ACN)

published 4mo ago modified 6d ago also EUVD-2026-117599 , GHSA-825c-7h77-2jjq

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository esa/asn1scc. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
8.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

Summary

ASN1SCC is an open source ASN.1 compiler for embedded systems. Prior to 4.7.0.1, BitStream_DecodeConstraintWholeNumber in asn1crt/asn1crt_encoding.c reads enough bits for a constrained integer but does not reject values above the declared range when the encoded range is not a power of two. Generated uPER and ACN decoders for variable-size SEQUENCE OF, OCTET STRING, BIT STRING, and string values use the invalid result as a loop or copy length, so a crafted over-range size field can write beyond a destination buffer. Decoding untrusted affected data can corrupt heap or stack memory, cause a crash, or potentially permit code execution. This issue is fixed in version 4.7.0.1.

Patch / fix

Is CVE-2026-75614 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
6d ago

Exploit prediction

0.58% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/esa/asn1scc/security/advisories/GHSA-825c-7h77-2jjq referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • esa asn1scc

Classification

Weakness
  • CWE-129 Improper Validation of Array Index
  • CWE-787 Out-of-bounds Write

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of esa/asn1scc published their own advisory on GitHub. Reviewed sources take precedence over it.