CVE-2023-25824 | mod_gnutls contains Infinite Loop on request read timeout

Exp

Mod_gnutls is a TLS module for Apache HTTPD based on GnuTLS. Versions from 0.9.0 to 0.12.0 (including) did not properly fail blocking read operations on TLS connections when the transport hit timeouts. Instead it entered an endless loop retrying the read operation, consuming CPU resources. This could be exploited for denial of service attacks. If trace level logging was enabled, it would also produce an excessive amount of log output during the loop, consuming disk space. The problem has been fixed in commit d7eec4e598158ab6a98bf505354e84352f9715ec, please update to version 0.12.1. There are no workarounds, users who cannot update should apply the errno fix detailed in the security advisory.

Published: 2023-02-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-25824 is rated High Exploit Risk (70.1/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.69%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2023-25824

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-25824

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 2026-04-17 0.77% 0.69% -0.08%
2 2026-02-26 0.95% 0.77% -0.18%
3 2026-02-25 0.95%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-25824

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-2023-25824

OS Trackers for CVE-2023-25824

vendor priority summary link
ubuntu medium CVE-2023-25824 medium priority: Ubuntu including 1 source packages (mod-gnutls), 13 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 4, ignored 3, not-affected 3, needed 2, needs-triage 1. https://ubuntu.com/security/CVE-2023-25824

Affected software / configurations for CVE-2023-25824

Vendor Product Version Raw CPE
mod_gnutls_project mod_gnutls >= 0.9.0, < 0.12.1 cpe:2.3:a:mod_gnutls_project:mod_gnutls:*:*:*:*:*:*:*:*

References for CVE-2023-25824

cvelogic Threat Intelligence