CVEs / CVE-2023-4911
CVE-2023-4911: GNU C Library Buffer Overflow Vulnerability
- Known exploited in the CISA KEV catalog since 21 Nov 2023
- high 7.8 CVSS 3.1 (NVD)
- EPSS 63.7% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
GNU C Library's dynamic loader ld.so contains a buffer overflow vulnerability when processing the GLIBC_TUNABLES environment variable, allowing a local attacker to execute code with elevated privileges.
Description
A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| from 2.34, before 2.39 | 2.39 | |
| Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | from V3.1.5 onwards | — |
| Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | from V3.1.5 onwards | — |
| Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem | before V1.1 | V1.1 |
| Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | from V3.1.5 onwards | — |
Exploitation
| In CISA KEV since | 21 Nov 2023 |
|---|---|
| Due date for US federal agencies | 12 Dec 2023 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 7.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-122, CWE-787 |
References
- CVE-2023-4911 on NVD
- CVE-2023-4911 in the CISA KEV catalog
- https://sourceware.org/git/?p=glibc.git (cited by CISA)
- https://access.redhat.com/security/cve/cve-2023-4911 (cited by CISA)
- https://www.debian.org/security/2023/dsa-5514 (cited by CISA)
- CVE-2023-4911 on OSV
- https://access.redhat.com/errata/RHSA-2023:5453 Third Party Advisory
- https://access.redhat.com/errata/RHSA-2023:5454 Third Party Advisory
- https://access.redhat.com/errata/RHSA-2023:5455 Third Party Advisory
- https://access.redhat.com/errata/RHSA-2023:5476 Third Party Advisory
- https://access.redhat.com/errata/RHSA-2024:0033 Third Party Advisory
- https://access.redhat.com/security/cve/CVE-2023-4911 Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2238352 Issue Tracking, Patch
- https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txt Exploit, Third Party Advisory
- https://www.qualys.com/cve-2023-4911/ Third Party Advisory
- http://packetstormsecurity.com/files/174986/glibc-ld.so-Local-Privilege-Escalation.html Exploit, Third Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/176288/Glibc-Tunables-Privilege-Escalation.html Exploit, Third Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2023/Oct/11 Exploit, Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2023/10/03/2 Exploit, Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/03/3 Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/05/1 Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/13/11 Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/14/3 Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/14/5 Mailing List
- http://www.openwall.com/lists/oss-security/2023/10/14/6 Mailing List
- https://lists.fedoraproject.org/archives/list/[email protected]/message/4DBUQRRPB47TC3NJOUIBVWUGFHBJAFDL/ Mailing List
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.