CVE-2026-73637: apache software foundation apache http server Use After Free
Vulnerability summary
CVE-2026-73637 is a high (CVSS 7.3) Use After Free vulnerability in apache software foundation apache http server. EPSS estimates a 0.48% chance of exploitation in the next 30 days, higher than 40.2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 1Timeline
- 01-10-2026PublishedVulnerability first disclosed.
- 01-10-2026Last modifiedVulnerability information updated.
Description
Use after free in mod_auth_digest in Apache Software Foundation Apache HTTP Server before 2.4.69 on all platforms allows an unauthenticated remote client to cause authentication state corruption via concurrent Digest authentication requests when AuthDigestNcCheck is enabled or AuthDigestNonceLifetime is set to 0. Users are recommended to upgrade to version 2.4.69, which fixes this issue.
CVSS metrics
5 scores · 5 sources · 1 version- OSV · AlpineEcosystem advisory · calculated7.3HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- OSV · UbuntuEcosystem advisory · calculated7.3HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- OSV · DebianEcosystem advisory · calculated7.3HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- NVDNIST7.3HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS trend
Probability
0.48%
Chance of exploitation in the next 30 days
Percentile
40%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Alpine1 product
- apache2< 2.4.69-r0
Apache1 product
- http_server≥ 2.4.0, < 2.4.69
Apache software foundation1 product
- apache http server≥ 2.4.0, ≤ 2.4.68
Debian1 product
- apache2All versions (No fix recorded) | < 2.4.69-1~deb13u1 | < 2.4.69-1
Ubuntu1 product
- apache2All versions (No fix recorded) | < 2.4.7-1ubuntu4.22+esm17 | < 2.4.18-2ubuntu3.17+esm22 | < 2.4.29-1ubuntu4.27+esm13 | < 2.4.41-4ubuntu3.23+esm9 | < 2.4.52-1ubuntu4.25 | < 2.4.58-1ubuntu8.17 | < 2.4.66-2ubuntu2.6
5 vendors · 5 products