Apache HTTP Server: buffer overflow in mod_proxy_ajp via ajp_msg_check_header()
Summary
| CVE | CVE-2026-28780 |
|---|---|
| State | PUBLISHED |
| Assigner | apache |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-05 22:16:00 UTC |
| Updated | 2026-07-09 13:16:54 UTC |
| Description | Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp and cause it to write 4 attacker controlled bytes after the end of a heap based buffer. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue. |
Risk And Classification
Primary CVSS: v3.1 9.8 CRITICAL from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.013760000 probability, percentile 0.688280000 (date 2026-07-12)
Problem Types: CWE-122 | CWE-787 | CWE-122 CWE-122 Heap-based Buffer Overflow | CWE-787 Out-of-bounds Write
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | ADP | CVSS | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Apache | Http Server | All | All | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:22140 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36846 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| httpd.apache.org/security/vulnerabilities_24.html | [email protected] | httpd.apache.org | Release Notes, Vendor Advisory |
| access.redhat.com/errata/RHSA-2026:36831 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| access.redhat.com/errata/RHSA-2026:21391 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:21433 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:27201 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-28780 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:27200 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| www.openwall.com/lists/oss-security/2026/05/05/9 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List, Third Party Advisory |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28780.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36373 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Andrew Lacambra (en)
CNA: Elhanan Haenel (en)
CNA: Tianshuo Han (<[email protected]>) (en)
CNA: Tristan Madani (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-02-04T12:00:00.000Z | reported |
| CNA | 2026-03-18T12:00:00.000Z | reported by 3rd finder |
| CNA | 2026-02-28T12:00:00.000Z | reported by 2nd finder |
| ADP | 2026-05-05T22:01:12.666Z | Reported to Red Hat. |
| ADP | 2026-05-05T21:29:41.527Z | Made public. |
Solutions
ADP: RHSA-2026:27200: Red Hat JBoss Core Services on RHEL 7 Server, Red Hat JBoss Core Services on RHEL 8
ADP: RHSA-2026:21433: Red Hat Enterprise Linux AppStream (v. 10)
ADP: RHSA-2026:22140: Red Hat Enterprise Linux AppStream (v. 8)
ADP: RHSA-2026:36846: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)
ADP: RHSA-2026:36831: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
ADP: RHSA-2026:36373: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)
ADP: RHSA-2026:21391: Red Hat Enterprise Linux AppStream (v. 9)
ADP: RHSA-2026:27201: Red Hat JBoss Core Services 2.4.62.SP4