CVE-2024-24814 | Denial of service when manipulating mod_auth_openidc_session_chunks cookie in mod_auth_openidc

Exp

mod_auth_openidc is an OpenID Certified™ authentication and authorization module for the Apache 2.x HTTP server that implements the OpenID Connect Relying Party functionality. In affected versions missing input validation on mod_auth_openidc_session_chunks cookie value makes the server vulnerable to a denial of service (DoS) attack. An internal security audit has been conducted and the reviewers found that if they manipulated the value of the mod_auth_openidc_session_chunks cookie to a very large integer, like 99999999, the server struggles with the request for a long time and finally gets back with a 500 error. Making a few requests of this kind caused our server to become unresponsive. Attackers can craft requests that would make the server work very hard (and possibly become unresponsive) and/or crash with minimal effort. This issue has been addressed in version 2.4.15.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-02-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-24814 is rated High Exploit Risk (68.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.25%). 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.05% over the last day, indicating growing attacker interest. 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-2024-24814

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

Exploit prediction scoring system (EPSS) score for CVE-2024-24814

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 0.21% 1.25% +1.05%
2 2025-12-30 0.29% 0.21% -0.09%
3 2025-12-28 — 0.29% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-24814

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-2024-24814

OS Trackers for CVE-2024-24814

vendor priority summary link
debian not yet assigned CVE-2024-24814 not yet assigned priority: Debian including 1 source packages (libapache2-mod-auth-openidc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2024-24814
redhat medium — https://access.redhat.com/security/cve/CVE-2024-24814
suse high CVE-2024-24814 severity important: SUSE including 10 source package names (apache2-mod_auth_openidc-2.3.8-150100.3.28.1, apache2-mod_auth_openidc-2.3.8-150600.16.5.1, …), 28 product×package rows across 26 product lines (SUSE Enterprise Storage 7.1, SUSE Liberty Linux 8, … (26 product lines)): Fixed 28. https://www.suse.com/security/cve/CVE-2024-24814/
ubuntu medium CVE-2024-24814 medium priority: Ubuntu including 1 source packages (libapache2-mod-auth-openidc), 11 status rows across 11 suites (bionic, focal, jammy, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): needed 4, not-affected 4, DNE 1, ignored 1, released 1. https://ubuntu.com/security/CVE-2024-24814

Affected software / configurations for CVE-2024-24814

Vendor Product Version Raw CPE
openidc mod_auth_openidc >= 2.0.0, <= 2.4.15.1 cpe:2.3:a:openidc:mod_auth_openidc:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
fedoraproject fedora 39 cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*

References for CVE-2024-24814

cvelogic Threat Intelligence