CVE-2026-6554 (GCVE-0-2026-6554)

Vulnerability from cvelistv5 – Published: 2026-09-05 18:51 – Updated: 2026-10-22 20:08
VLAI
Title
infinte loop in libpcap before 1.10.7
Summary
libpcap BPF interpreter treats the offset in the 'ja L' BPF instruction as a signed integer to implement looping via backward jumps, but it does not limit the number of loop iterations. A crafted filter program or the 'protochain' primitive used on a crafted network packet can cause the interpreter to loop infinitely.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 15:14 UTC
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
Tcpdump CNA under the mitre root
CNA scorecard – unranked: 7 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
The Tcpdump Group libpcap Affected: 0 , < 1.10.7 (semver)
guessed Create a notification for this product.
Credits
Kaixuan LI has discovered the crafted filter program attack vector Denis Ovsienko has discovered the 'protochain' attack vector
Show details on NVD website
To clipboard 

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