Vulnerability-Lookup

CVE-2026-121995 (GCVE-0-2026-121995)

Vulnerability from cvelistv5 – Published: 2026-11-05 16:08 – Updated: 2026-11-09 17:18

Title

Gdb: gdb: stack buffer overflow in parse_tracepoint_definition via stale rs->buf tail

Summary

A stack buffer overflow in the GDB client's tracepoint upload handler allows an attacker-controlled debug stub to corrupt stack memory automatically during connection setup. The overflow results from GDB reading beyond the current reply boundary into a stale prior reply in the shared packet buffer.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-11-09 17:17 UTC

CWE

CWE-121 - Stack-based Buffer Overflow

Assigner

redhat CNA

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-121995	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2565677	issue-trackingx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/a:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:rhel_els:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:rhel_els:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/a:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/a:redhat:enterprise_linux:9
Red Hat	Red Hat Hardened Images	cpe:/a:redhat:hummingbird:1

Date Public

2026-11-05 14:29

Credits

Red Hat would like to thank Pulkit Singh Singaria for reporting this issue.

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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CVE-2026-121995 (GCVE-0-2026-121995)

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