Stack Buffer Overflow
Source GCVE Database
Not known to be exploited · CVSS 7.5 High.
Data as of 5 Nov 2026, 19:36 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.5 |
|---|
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10crash | Affected– | Fixed in– |
| Red Hat Enterprise Linux 10gdb | Affected– | Fixed in– |
| Red Hat Enterprise Linux 6gdb | Affected– | Fixed in– |
| Red Hat Enterprise Linux 7gdb | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8crash | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8gcc-toolset-14-gdb | Affected– | Fixed in– |
AI-suggested
Users should only connect GDB to trusted debug targets to avoid exploitation. No other mitigations are provided by the vendor.
Description
CVE-2026-121995 is a stack buffer overflow vulnerability in the GDB client's tracepoint upload handler. It occurs during the target remote connection handshake when the remote debug stub reports tracepoint support. This overflow results from GDB reading beyond the current reply boundary into stale data in the shared packet buffer, leading to automatic stack memory corruption. The vulnerability requires user interaction to initiate the connection and has a high complexity for exploitation due to stack canary protections. There is no available patch or mitigation other than connecting GDB only to trusted debug targets.