CVE-2026-34356: apache software foundation apache http server Heap-based Buffer Overflow
CVSS: 7.5v3.1HighAnalyzed
AliasesALPINE-CVE-2026-34356UBUNTU-CVE-2026-34356DEBIAN-CVE-2026-34356
Published 08-06-2026Last modified 08-06-2026
Vulnerability summary
CVE-2026-34356 is a high (CVSS 7.5) Heap-based Buffer Overflow vulnerability in apache software foundation apache http server. EPSS estimates a 1.21% chance of exploitation in the next 30 days, higher than 67.9% of scored vulnerabilities.
CVSS score
7.5/10
010
High · v3.1 (CVE.org)EPSS score
1.21%
0%100%
Low · +0.50 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 18 · Related 8Timeline
- 08-06-2026PublishedVulnerability first disclosed.
- 08-06-2026Last modifiedVulnerability information updated.
Description
Heap-based Buffer Overflow vulnerability in Apache HTTP Server with malicious backend servers and ProxyPassReverseCookie* This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
CVSS metrics
5 scores · 5 sources · 1 versionHigh 7.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 5 agree
- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.21%
Chance of exploitation in the next 30 days
Percentile
68%
Versus all other CVEs
30-day change
+0.50 pp
From 0.71% on 18-09-2026
18-09-202618-10-2026
EPSS score1.21%
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< 2.4.68-r0
Apache1 product
- http_server≥ 2.4.0, < 2.4.68
Apache software foundation1 product
- apache http server≥ 2.4.0, ≤ 2.4.67
Debian1 product
- apache2< 2.4.68-1~deb12u1 | < 2.4.68-1~deb13u1 | < 2.4.68-1
Ubuntu1 product
- apache2< 2.4.7-1ubuntu4.22+esm14 | < 2.4.18-2ubuntu3.17+esm19 | < 2.4.29-1ubuntu4.27+esm10 | < 2.4.41-4ubuntu3.23+esm5 | < 2.4.52-1ubuntu4.23 | < 2.4.58-1ubuntu8.15 | All versions (No fix recorded) | < 2.4.66-2ubuntu2.4
5 vendors · 5 products
