{"id":"CVE-2023-4911","published":"2023-10-03T18:15:10Z","modified":"2026-10-14T22:17:18Z","title":"GNU C Library Buffer Overflow Vulnerability","vendor":"GNU","product":"GNU C Library","tier":"core","eol":null,"description":{"text":"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.","provenance":"source","from":"NVD"},"summary":{"text":"A buffer overflow in the dynamic loader ld.so of the GNU C Library (GLIBC) is triggered while it parses the GLIBC_TUNABLES environment variable. An attacker with local access and low privileges can craft a malicious GLIBC_TUNABLES value to run code with elevated privileges when a SUID binary is launched, and no user interaction is required.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:10:49Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.63769,"percentile":0.99219,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2023-11-21","dueDate":"2023-12-12","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","notes":"This vulnerability affects a common open-source component, third-party library, or a protocol used by different products. Please check with specific vendors for information on patching status. For more information, please see: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=1056e5b4c3f2d90ed2b4a55f96add28da2f4c8fa, https://access.redhat.com/security/cve/cve-2023-4911, https://www.debian.org/security/2023/dsa-5514 ; https://nvd.nist.gov/vuln/detail/CVE-2023-4911  ","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-11-03","exploitedFirstSeen":"2023-11-03","ransomware":true,"evidence":[{"url":"https://blog.aquasec.com/loony-tunables-vulnerability-exploited-by-kinsing","date":"2023-11-03"},{"url":"https://www.trendmicro.com/en_us/research/23/k/cve-2023-46604-exploited-by-kinsing.html","date":"2023-11-20"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2023-11-21"},{"url":"https://www.sentinelone.com/resources/watchtower-end-of-year-report-2023/","date":"2024-01-31"},{"url":"https://go.recordedfuture.com/hubfs/reports/ta-2024-0321.pdf","date":"2024-03-21"},{"url":"https://bi.zone/upload/for_download/Threat_Zone_2024_BI.ZONE_Research_rus.pdf","date":"2024-04-04"},{"url":"https://www.trustwave.com/hubfs/Web/Library/Documents_pdf/2024_Trustwave_Professional_Services_Sector_Threat_Landscape.pdf","date":"2024-06-26"},{"url":"https://securelist.com/exploits-and-vulnerabilities-q3-2024/114839/","date":"2024-12-06"},{"url":"https://www.loginsoft.com/reports/annually/vulnerability-intelligence-report-2025","date":"2026-01-20"}],"evidenceTotal":9,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"}],"provenance":"machine"},"cwes":[{"id":"CWE-787","name":"Out-of-bounds Write"},{"id":"CWE-122","name":"Heap-based Buffer Overflow"}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2023:5453","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5454","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5455","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5476","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2024:0033","tags":["Third Party 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List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/03/3","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/05/1","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/13/11","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/14/3","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/14/5","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/10/14/6","tags":["Mailing List"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5453","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5454","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5455","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2023:5476","tags":["Third Party Advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2024:0033","tags":["Third Party 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