CVE-2026-15712
A heap buffer over-read vulnerability was discovered in libsoup's (versions: libsoup 3.0 to 3.7.0) HTTP/2 connection tracking framework. When the library processes an HTTP/2 GOAWAY frame, it improperly handles the "Additional Debug Data" payload by assuming the data stream is a safely NUL-terminated C-string. Because the parser lacks strict length-boundary verification before reading this data, a remote, unauthenticated attacker can intentionally send a malformed GOAWAY frame missing the appropriate null delimiter. This causes the library to read past the end of the allocated buffer, triggering an application crash that results in a denial of service (DoS), or potentially exposing fragments of memory contents.
CSIRTS triage
- What
- A heap buffer over-read occurs during HTTP/2 goaway frame parsing due to an invalid null-termination assumption.
- Who is affected
- Deployments using libsoup3 are affected by this vulnerability.
- Urgency
- This is a medium urgency issue as it may lead to unexpected behavior.
- Action
- Update libsoup to the latest version to mitigate this vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.50% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all EPSS-scored CVEs.
Advisory coverage (2)
External references
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