CVE-2026-121994
Gdb: gdb: stack buffer overflow in fetch_register_using_p via unchecked p-reply length
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Gdb: gdb: stack buffer overflow in fetch_register_using_p via unchecked p-reply length
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
CVE-2026-121994- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-06
EUVDEUVD-2026-117571
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
EUVD-2026-117571- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-06
GitHub AdvisoriesGHSA-8xgh-vfg7-p2g8
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled...
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
GHSA-8xgh-vfg7-p2g8- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-05
NVD
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
CVE-2026-121994- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-06
OSVDEBIAN-CVE-2026-121994
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
DEBIAN-CVE-2026-121994- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-06
OSVUBUNTU-CVE-2026-121994
A stack buffer overflow in the GDB client's remote protocol handler allows an attacker-controlled debug target to execute arbitrary code in the GDB process. The vulnerability exists in fetch_register_using_p, which decodes a stub's register reply into an alloca-sized buffer without bounding writes by the register width.
- Record
UBUNTU-CVE-2026-121994- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-07
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gdbDebian:12 |
All versions, plus listed versions 13.1-313.2-113.2-1+hurd.315.1-115.2-1 Show 36 moreShow less15.2-2~exp116.0.90.20250111-1~exp116.0.90.20250111-1~exp216.1-116.1-216.1-2+hurd.116.2-116.2-216.2-316.2-416.2-516.2-616.2-716.2-816.3-116.3-216.3-316.3-416.3-4~bpo13+116.3-4~bpo13+216.3-516.3-5~bpo13+117.0.50.20250905-1~exp117.0.90-1~exp117.0.90-1~exp217.1-117.1-1~bpo13+117.1-217.1-317.1-417.2-117.2-1~bpo13+118.1-118.1-218.1-318.1-3~bpo13+1 |
None known |
gdbDebian:13 |
All versions, plus listed versions 16.3-116.3-216.3-316.3-416.3-4~bpo13+1 Show 17 moreShow less16.3-4~bpo13+216.3-516.3-5~bpo13+117.0.50.20250905-1~exp117.0.90-1~exp117.0.90-1~exp217.1-117.1-1~bpo13+117.1-217.1-317.1-417.2-117.2-1~bpo13+118.1-118.1-218.1-318.1-3~bpo13+1 |
None known |
gdbDebian:14 |
All versions, plus listed versions 16.3-116.3-216.3-316.3-416.3-4~bpo13+1 Show 17 moreShow less16.3-4~bpo13+216.3-516.3-5~bpo13+117.0.50.20250905-1~exp117.0.90-1~exp117.0.90-1~exp217.1-117.1-1~bpo13+117.1-217.1-317.1-417.2-117.2-1~bpo13+118.1-118.1-218.1-318.1-3~bpo13+1 |
None known |
gdbUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 7.10-1ubuntu27.10-1ubuntu37.10.1-0ubuntu17.10.90.20160215-0ubuntu27.10.90.20160220-0ubuntu1 Show 4 moreShow less7.11-0ubuntu17.11.1-0ubuntu1~16.047.11.1-0ubuntu1~16.57.11.1-0ubuntu1~16.5+esm1 |
None known |
gdbUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 8.0.1-0ubuntu18.0.1-0ubuntu28.0.1-0ubuntu38.1-0ubuntu18.1-0ubuntu2 Show 5 moreShow less8.1-0ubuntu38.1-0ubuntu3.18.1-0ubuntu3.28.1.1-0ubuntu18.1.1-0ubuntu1+esm1 |
None known |
gdbUbuntu:20.04:LTS |
All versions, plus listed versions 8.3-0ubuntu19.0.50.20191019-0ubuntu19.0.50.20191119-0ubuntu19.0.90.20191216-0ubuntu19.0.90.20200105-0ubuntu1 Show 5 moreShow less9.0.90.20200117-0ubuntu19.1-0ubuntu19.2-0ubuntu1~20.049.2-0ubuntu1~20.04.19.2-0ubuntu1~20.04.2 |
None known |
gdbUbuntu:22.04:LTS |
All versions, plus listed versions 11.1-0ubuntu211.1-0ubuntu311.2-0ubuntu112.0.50.20220217-0ubuntu112.0.90-0ubuntu112.1-0ubuntu1~22.0412.1-0ubuntu1~22.04.2 |
None known |
gdbUbuntu:24.04:LTS |
All versions, plus listed versions 14.0.50.20230907-0ubuntu114.1-0ubuntu114.1-0ubuntu215.0.50.20240219-0ubuntu115.0.50.20240320-0ubuntu115.0.50.20240403-0ubuntu115.1-1ubuntu1~24.04.1 |
None known |
gdbUbuntu:26.10 |
All versions, plus listed versions 17.1-2ubuntu117.2-1ubuntu1 |
None known |
gdbUbuntu:26.04:LTS |
All versions, plus listed versions 16.3-1ubuntu216.3-5ubuntu117.1-1ubuntu117.1-1ubuntu217.1-2ubuntu1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | CVE List, EUVD, OSV | |
| affected, aliases, references | CVE List, EUVD, NVD, OSV | |
| aliases, references | GitHub Advisories | |
| aliases, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-121994 is a high vulnerability (CVSS 8.8) in Red Hat Enterprise Linux 10, published November 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.48%, the 41st percentile. No source names a fixed version.