CVE-2026-121944 (GCVE-0-2026-121944)
Vulnerability from cvelistv5 – Published: 2026-11-04 12:31 – Updated: 2026-11-04 18:51
VLAI
EPSS
VEX
Title
sngrep through 1.9.0 Infinite Loop DoS via Crafted NFLOG TLV
Summary
sngrep through 1.9.0 contains an infinite loop vulnerability in capture_packet_reasm_ip() in src/capture.c that allows attackers to cause denial of service via crafted NFLOG TLVs. Attackers can supply a pcap file with link type NFLOG containing a non-payload TLV with length under 4, making the capture thread spin at full CPU and stop processing packets.
Severity
5.5 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-04 18:50 UTC
CWE
- CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
VulnCheck
CNA
References
5 references
| URL | Tags |
|---|---|
| https://github.com/irontec/sngrep/issues/589 | issue-tracking |
| https://hackmd.io/@haindpwn/sngrep-sip-payload-mi… | third-party-advisory |
| https://github.com/irontec/sngrep/blob/v1.9.0/src… | technical-description |
| https://www.vulncheck.com/advisories/sngrep-throu… | third-party-advisory |
| https://hackmd.io/@haindpwn/cve-2026-121943-12194… | exploit |
Impacted products
Date Public
2026-10-21 13:36
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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