Answer in brief
CVE-2026-121626 records a Medium severity (CVSS 6.3) vulnerability in GNU Gatekeeper before 5.16 Out-of-Bounds Read in H.460.24 RTCP Probe Handler. The current sources do not mark it as known exploited. The current feed maps willamowius/gnugk (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps willamowius/gnugk (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| willamowius/gnugkgeneric | >=0 <5.16 | 5.16 |
Published upstream
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 3, 2026
GNU Gatekeeper (gnugk) before 5.16 contains an out-of-bounds read vulnerability in H46024Socket::ReceivedProbePacket() that allows remote attackers to cause a heap over-read by sending short probe packets. Attackers can send a short application-defined RTCP packet to the media port during H.460.24 probing to read past the heap allocation and possibly crash the gatekeeper.
Quoted source text, attributed separately from HOL analysis.