libks has path traversal in kws HTTP parser via URI segment overflow

published 2026-06-03 5mo ago modified 2026-09-30 last mo. also EUVD-2026-76756 , GHSA-684h-wjm9-2p6j

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository signalwire/libks. 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: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits: 0; none known

libks provides foundational support for signalwire C products. Prior to version 2.0.11, `clean_uri()` in libks's HTTP request parser fails to reject URIs whose path has more segments than its internal canonicalization buffer can hold. The canonicalization step silently passes such URIs through with embedded ".." sequences intact, enabling path traversal in any consumer that later joins the URI with a filesystem path. Version 2.0.11 patches the issue.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: last mo. (2026-09-15)

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

signalwire libks

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory
CWE-697 Incorrect Comparison

References

github.com /signalwire/libks/security/advisories/GHSA-684h-wjm9-2p6j
advisory

Sources

CVE List CVE-2026-49846
NVD CVE-2026-49846
Maintainer advisory GHSA-684h-wjm9-2p6j

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 signalwire/libks published their own advisory on GitHub. Reviewed sources take precedence over it.