Description
Passing an effectively empty string to the `,ccs=` syntax extension of the mode argument in the `fopen` function in the GNU C Library version 2.45 or earlier may result in a heap buffer overflow when the mode string input to the function is attacker controlled.
This usage pattern is not seen in applications in common GNU/Linux distributions and applications that process user-supplied values for `ccs` should not pass them through without validation.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The GNU C Library | glibc | < 2.45 | 2.45 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | glibc | 2.43-5 | — |
| Debian 13 | glibc | No fix yet | — |
| Debian 12 | glibc | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | glibc | 2.44-1ubuntu2.1 | USN-9065-1 |
| Ubuntu 26.04 LTS | glibc | 2.43-2ubuntu2.7 | USN-9065-1 |
| Ubuntu 24.04 LTS | glibc | 2.39-0ubuntu8.12 | USN-9065-1 |
| Ubuntu 22.04 LTS | glibc | 2.35-0ubuntu3.18 | USN-9065-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | glibc | No fix yet | — |
| Ubuntu Pro 18.04 LTS | glibc | No fix yet | — |
| Ubuntu Pro 16.04 LTS | glibc | No fix yet | — |
| Ubuntu Pro 14.04 LTS | eglibc | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | glibc +220 | 2.39-145.el10_2 | RHSA-2026:84753 |
| RHEL 9 | nscd +214 | 2.34-283.el9_8 | RHSA-2026:79281 |
| RHEL 8 | nscd +213 | 2.28-251.el8_10.48 | RHSA-2026:80798 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | glibc +227 | 2.43-8.5.hum1 | RHSA-2026:65339 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | glibc +220 | 2.39-145.el10_2.alma.1 | ALSA-2026:84753 |
| AlmaLinux 9 | nscd +214 | 2.34-283.el9_8 | ALSA-2026:79281 |
| AlmaLinux 8 | nscd +211 | 2.28-251.el8_10.48 | ALSA-2026:80798 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | glibc | 2.39-145.el10_2 | RLSA-2026:84753 |
| Rocky Linux 9 | glibc | 2.34-283.el9_8 | RLSA-2026:79281 |
| Rocky Linux 8 | glibc | 2.28-251.el8_10.48 | RLSA-2026:80798 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | glibc | 2.38-150600.14.58.1 | SUSE-SU-2026:4250-1 |
| SLES 15 SP6 | glibc | 2.38-150600.14.58.1 | SUSE-SU-2026:4250-1 |
| SLES 15 SP5 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLES 15 SP4 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLES 12 SP5 | glibc | 2.22-114.52.2 | SUSE-SU-2026:4204-1 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | glibc | 2.40-160000.7.1 | SUSE-SU-2026:23934-1 |
| SLES for SAP 15 SP6 | glibc | 2.38-150600.14.58.1 | SUSE-SU-2026:4250-1 |
| SLES for SAP 15 SP5 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLES for SAP 15 SP4 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLES 16.0 | glibc | 2.40-160000.7.1 | SUSE-SU-2026:23934-1 |
| SLE Micro 6.2 | glibc | 2.40-160000.7.1 | SUSE-SU-2026:23957-1, SUSE-SU-2026:23929-1 |
| SLE Micro 6.1 | glibc | 2.38-slfo.1.1_10.1 | SUSE-SU-2026:23738-1 |
| SLE Micro 6.0 | glibc | 2.38-15.1 | SUSE-SU-2026:23830-1 |
| SLE Micro 5.5 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLE Micro 5.4 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLE Micro 5.3 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLE HPC 15 SP5 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
| SLE HPC 15 SP4 | glibc | 2.31-150300.109.1 | SUSE-SU-2026:4591-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | glibc | 2.44-2.1 | openSUSE-SU-2026:11787-1 |
| openSUSE Leap 16.0 | glibc +4 | 2.40-160000.7.1 | openSUSE-SU-2026:21968-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | glibc | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | glibc +220 | 2.39-145.0.1.el10_2 | ELSA-2026-84753 |
| Oracle Linux 9 | nscd +214 | 2.34-283.0.1.el9_8 | ELSA-2026-79281 |
| Oracle Linux 8 | nscd +213 | 2.28-251.0.5.el8_10.48 | ELSA-2026-80798 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | sln-2.43 +26 | 2.43-r18 | — |
| Wolfi rolling | sln-2.44 +26 | 2.44-r6 | — |
Advisories 25
- USN-9065-1 glibc vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- WID-SEC-2026-3063 GNU libc: Schwachstelle ermöglicht nicht spezifizierten Angriff BSI CERT-Bund (WID) · Nov 12, 2026
- ELSA-2026-80798 Moderate: glibc security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Nov 3, 2026
- ELSA-2026-84753 Moderate: glibc security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Nov 2, 2026
- ELSA-2026-79281 Moderate: glibc security, bug fix, and enhancement update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Nov 2, 2026
- ALSA-2026:79281 Moderate: glibc security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:84753 Moderate: glibc security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:80798 Moderate: glibc security update AlmaLinux Security Advisories · Oct 29, 2026
- RLSA-2026:84753 Moderate: glibc security update Rocky Linux Security Advisories · Oct 20, 2026
- RHSA-2026:84753 Red Hat Security Advisory: glibc security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:80798 Red Hat Security Advisory: glibc security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:79281 Red Hat Security Advisory: glibc security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:65339 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RLSA-2026:80798 Moderate: glibc security update Rocky Linux Security Advisories · Oct 14, 2026
- RLSA-2026:79281 Moderate: glibc security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 10, 2026
- SUSE-SU-2026:4591-1 Security update for glibc SUSE / openSUSE Security Updates · Oct 9, 2026
- SUSE-SU-2026:23957-1 Security update for glibc SUSE / openSUSE Security Updates · Oct 2, 2026
- SUSE-SU-2026:23929-1 Security update for glibc SUSE / openSUSE Security Updates · Oct 2, 2026
- SUSE-SU-2026:23934-1 Security update for glibc SUSE / openSUSE Security Updates · Oct 2, 2026
- openSUSE-SU-2026:21968-1 Security update for glibc SUSE / openSUSE Security Updates · Oct 1, 2026
- SUSE-SU-2026:23830-1 Security update for glibc SUSE / openSUSE Security Updates · Sep 27, 2026
- SUSE-SU-2026:23738-1 Security update for glibc SUSE / openSUSE Security Updates · Sep 27, 2026
- SUSE-SU-2026:4250-1 Security update for glibc SUSE / openSUSE Security Updates · Sep 18, 2026
- SUSE-SU-2026:4204-1 Security update for glibc SUSE / openSUSE Security Updates · Sep 16, 2026
- openSUSE-SU-2026:11787-1 glibc-2.44-2.1 on GA media SUSE / openSUSE Security Updates · Sep 16, 2026