CVE-2023-5156 | Glibc: dos due to memory leak in getaddrinfo.c

A flaw was found in the GNU C Library. A recent fix for CVE-2023-4806 introduced the potential for a memory leak, which may result in an application crash.

Published: 2023-09-25 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-5156 is rated Moderate Risk (54.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.34%). EPSS rose +1.28% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-5156

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 1.34% +1.28%
2 2025-11-21 0.76% 0.06% -0.70%
3 2025-11-18 — 0.76% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-5156

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-5156

OS Trackers for CVE-2023-5156

vendor priority summary link
debian unimportant CVE-2023-5156 unimportant priority: Debian including 1 source packages (glibc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2023-5156
gentoo high CVE-2023-5156: 1 GLSA(s) (202402-01), 1 atom(s) (sys-libs/glibc); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2023-5156
redhat medium — https://access.redhat.com/security/cve/CVE-2023-5156
suse low CVE-2023-5156 severity low: SUSE including 73 source package names (glibc, glibc-2.38-150600.12.1, …), 394 product×package rows across 47 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 7.1, … (47 product lines)): Known Not Affected 339, Fixed 55. https://www.suse.com/security/cve/CVE-2023-5156/
ubuntu medium CVE-2023-5156 medium priority: Ubuntu including 2 source packages (eglibc, glibc), 24 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 10, released 7, not-affected 3, needs-triage 2, deferred 1, ignored 1. https://ubuntu.com/security/CVE-2023-5156

Affected software / configurations for CVE-2023-5156

Vendor Product Version Raw CPE
gnu glibc >= 2.34, < 2.39 cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*

References for CVE-2023-5156

cvelogic Threat Intelligence