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CVE-2026-129126 C-Kermit before 11.1.515 Heap Buffer Overflow via putsrv() Packet Decoding

9.2 critical

Critical (9.2) in openkermit c-kermit.

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C-Kermit before 11.1.515 contains a heap buffer overflow vulnerability in putsrv() in ckcfns.c that allows malicious peers to write past the srvcmd buffer by sending crafted packets. Attackers can use Kermit repeat-count compression in server command, GET, or file-header packets to write attacker-chosen bytes beyond the heap buffer on servers or receiving instances.

Severity

CVSS 4.0

9.2 critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

8.1 high
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-122 Heap-based Buffer Overflow
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
OpenKermit C-Kermitbefore 11.1.515

Attack patterns (CAPEC)

  • CAPEC-92 Forced Integer Overflow Likelihood: High · Severity: High

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

History

  1. The NVD deferred its analysis

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

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