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Fencer Vulns
critical 9.8

CVE-2026-28780 in the critical feed json

Apache HTTP Server: buffer overflow in mod_proxy_ajp via ajp_msg_check_header()

published 2026-05-05 6 mo ago modified 2026-09-15 54 d ago also BIT-apache-2026-28780 , EUVD-2026-27506

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.4%
EPSS 1.4% chance of exploitation in 30 days, percentile 72%
public exploits
0
none known

Summary

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.

Patch / fix

  • bitnami apache 2.4.67
  • Red Hat JBoss Core Services for RHEL 8 0:2.4.62-13.el8jbcs
  • Red Hat JBoss Core Services on RHEL 7 0:2.4.62-13.el7jbcs
  • Red Hat Red Hat Enterprise Linux 10 0:2.4.63-13.el10_2.1
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support 0:2.4.63-1.el10_0.4
  • Red Hat Red Hat Enterprise Linux 8 8100020260519200905.489197e6
  • Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support 8040020260702193120.522a0ee4
  • Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On 8040020260702193120.522a0ee4
  • Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support 8060020260702195216.ad008a3a
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On 8060020260702195216.ad008a3a
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service 8080020260702200145.63b34585
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions 8080020260702200145.63b34585
  • Red Hat Red Hat Enterprise Linux 9 0:2.4.62-13.el9_8.1
  • Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions 0:2.4.57-11.el9_4.5
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support 0:2.4.62-4.el9_6.6
  • apache2 Debian 12 2.4.67-1~deb12u2
  • apache2 Debian 13 2.4.67-1~deb13u2
  • apache2 Debian 14 2.4.67-1

debian advisories DEBIAN-CVE-2026-28780

  • apache2 Ubuntu 22.04 LTS 2.4.52-1ubuntu4.20
  • apache2 Ubuntu 24.04 LTS 2.4.58-1ubuntu8.12
  • apache2 Ubuntu 25.10 2.4.64-1ubuntu3.4
  • apache2 Ubuntu 26.04 LTS 2.4.66-2ubuntu2.1
  • apache2 Ubuntu Pro 14.04 LTS 2.4.7-1ubuntu4.22+esm13
  • apache2 Ubuntu Pro 16.04 LTS 2.4.18-2ubuntu3.17+esm18
  • apache2 Ubuntu Pro 18.04 LTS 2.4.29-1ubuntu4.27+esm9
  • apache2 Ubuntu Pro 20.04 LTS 2.4.41-4ubuntu3.23+esm4

ubuntu advisories UBUNTU-CVE-2026-28780

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • jbcs-httpd24-httpd jboss core services 1 2.4.62-13.el7jbcs
  • jbcs-httpd24-httpd jboss core services 1 2.4.62-13.el8jbcs
  • jbcs-httpd24-mod_md jboss core services 1 1:2.4.28-16.el7jbcs
  • jbcs-httpd24-mod_md jboss core services 1 1:2.4.28-16.el8jbcs
  • jbcs-httpd24-mod_ssl jboss core services 1 1:2.4.62-13.el7jbcs
  • jbcs-httpd24-mod_ssl jboss core services 1 1:2.4.62-13.el8jbcs
  • jbcs-httpd24-nghttp2 jboss core services 1 1.64.0-3.el7jbcs
  • jbcs-httpd24-nghttp2 jboss core services 1 1.64.0-3.el8jbcs

red hat advisories RHSA-2026:67152RHSA-2026:66323RHSA-2026:62165RHSA-2026:47046RHSA-2026:36846RHSA-2026:36831

  • apache2 SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 2.4.66-150400.6.57.1
  • apache2 SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2-event SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2-utils SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2-manual SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2-worker SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2-prefork SLES 16.0, SLES for SAP applications 16.0 2.4.66-160000.2.1
  • apache2 SLES LTSS Extended Security 12 SP5, SLES 12 SP5-LTSS 2.4.66-35.78.1

suse advisories SUSE-SU-2026:2641-1SUSE-SU-2026:2686-1SUSE-SU-2026:22199-1SUSE-SU-2026:22209-1

  • apache2 openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2-event openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2-utils openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2-manual openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2-worker openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2-prefork openSUSE Leap 16.0 2.4.66-160000.2.1
  • apache2 openSUSE Tumbleweed 2.4.67-1.1

opensuse advisories openSUSE-SU-2026:21115-1openSUSE-SU-2026:10785-1

  • httpd AlmaLinux 8 2.4.37-65.module_el8.10.0+4185+0955a0d7.8
  • mod_md AlmaLinux 8 1:2.0.8-8.module_el8.10.0+4088+57f011c1.2
  • mod_ssl AlmaLinux 8 1:2.4.37-65.module_el8.10.0+4185+0955a0d7.8
  • mod_ldap AlmaLinux 8 2.4.37-65.module_el8.10.0+4185+0955a0d7.8
  • mod_http2 AlmaLinux 8 1.15.7-10.module_el8.10.0+4185+0955a0d7.5
  • httpd-tools AlmaLinux 8 2.4.37-65.module_el8.10.0+4185+0955a0d7.8
  • mod_session AlmaLinux 8 2.4.37-65.module_el8.10.0+4185+0955a0d7.8
  • httpd-manual AlmaLinux 8 2.4.37-65.module_el8.10.0+4185+0955a0d7.8

almalinux advisories ALSA-2026:22140ALSA-2026:21391ALSA-2026:21433

  • httpd Rocky Linux 10 2.4.63-13.el10_2.1
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+2061+8d03fdec.5
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1830+22f0c9e0
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1938+3b7755d4.3
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1984+1bed3124.4
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1842+4a9649e8.2
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1840+b070a976.1
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+40053+5a18018e.7

rocky linux advisories RLSA-2026:21433RLSA-2026:22140RLSA-2026:21391

  • apache2 Alpine 3.24, Alpine 3.23, Alpine 3.22 +2 more 2.4.67-r0

alpine advisories ALPINE-CVE-2026-28780

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-28780 updated cvss 8.1

Apache HTTP Server: mod_proxy_ajp: Apache HTTP Server mod_proxy_ajp: Arbitrary code execution via heap-based buffer overflow

  • Red Hat Enterprise Linux 6 httpd, mod_ssl, httpd-tools, httpd-manual
    affected: no fix available
  • Red Hat Enterprise Linux AppStream (v. 8) mod_md 2.0.8-8.module+el8.10.0+23815+1b5e1c66.2, httpd 2.4.37-65.module+el8.10.0+24281+ea10630c.8, mod_ssl 2.4.37-65.module+el8.10.0+24281+ea10630c.8, mod_ldap 2.4.37-65.module+el8.10.0+24281+ea10630c.8, mod_http2 1.15.7-10.module+el8.10.0+24315+35fe59d0.5, httpd-tools 2.4.37-65.module+el8.10.0+24281+ea10630c.8, +4 more
    fixed: vendor fix RHSA-2026:22140
  • Red Hat Enterprise Linux AppStream (v. 9) httpd 2.4.62-13.el9_8.1, mod_lua 2.4.62-13.el9_8.1, mod_ssl 2.4.62-13.el9_8.1, mod_ldap 2.4.62-13.el9_8.1, httpd-core 2.4.62-13.el9_8.1, httpd-tools 2.4.62-13.el9_8.1, +4 more
    fixed: vendor fix RHSA-2026:21391
  • Red Hat Enterprise Linux AppStream (v. 10) httpd 2.4.63-13.el10_2.1, mod_lua 2.4.63-13.el10_2.1, mod_ssl 2.4.63-13.el10_2.1, mod_ldap 2.4.63-13.el10_2.1, httpd-core 2.4.63-13.el10_2.1, httpd-tools 2.4.63-13.el10_2.1, +4 more
    fixed: vendor fix RHSA-2026:21433
  • Red Hat Enterprise Linux AppStream AUS (v.8.4) mod_md 2.0.8-8.module+el8.4.0+23842+00253415.1, httpd 2.4.37-39.module+el8.4.0+24495+1afced82.12, mod_http2 1.15.7-3.module+el8.4.0+24495+1afced82.5, mod_ssl 2.4.37-39.module+el8.4.0+24495+1afced82.12, mod_ldap 2.4.37-39.module+el8.4.0+24495+1afced82.12, httpd-tools 2.4.37-39.module+el8.4.0+24495+1afced82.12, +4 more
    fixed: vendor fix RHSA-2026:36846
  • Red Hat Enterprise Linux AppStream AUS (v.8.6) mod_md 2.0.8-8.module+el8.6.0+23843+c27a5dc4.1, httpd 2.4.37-47.module+el8.6.0+24496+af8fe930.13, mod_http2 1.15.7-5.module+el8.6.0+24496+af8fe930.5, mod_ssl 2.4.37-47.module+el8.6.0+24496+af8fe930.13, mod_ldap 2.4.37-47.module+el8.6.0+24496+af8fe930.13, httpd-tools 2.4.37-47.module+el8.6.0+24496+af8fe930.13, +4 more
    fixed: vendor fix RHSA-2026:36831
  • Red Hat Enterprise Linux AppStream E4S (v.8.8) mod_md 2.0.8-8.module+el8.8.0+23840+d7e7db80.1, httpd 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, mod_http2 1.15.7-8.module+el8.8.0+24497+e470c0e2.7, mod_ssl 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, mod_ldap 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, httpd-tools 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, +4 more
    fixed: vendor fix RHSA-2026:36373
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) httpd 2.4.53-11.el9_2.15, httpd-core 2.4.53-11.el9_2.15
    fixed: vendor fix RHSA-2026:67152
show 10 more
  • Red Hat Enterprise Linux AppStream E4S (v.9.4) httpd 2.4.57-11.el9_4.5, httpd-core 2.4.57-11.el9_4.5
    fixed: vendor fix RHSA-2026:66323
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) httpd 2.4.63-1.el10_0.4, mod_lua 2.4.63-1.el10_0.4, mod_ssl 2.4.63-1.el10_0.4, mod_ldap 2.4.63-1.el10_0.4, httpd-core 2.4.63-1.el10_0.4, httpd-tools 2.4.63-1.el10_0.4, +4 more
    fixed: vendor fix RHSA-2026:47046
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) httpd 2.4.62-4.el9_6.6, mod_lua 2.4.62-4.el9_6.6, mod_ssl 2.4.62-4.el9_6.6, mod_ldap 2.4.62-4.el9_6.6, httpd-core 2.4.62-4.el9_6.6, httpd-tools 2.4.62-4.el9_6.6, +4 more
    fixed: vendor fix RHSA-2026:62165
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) mod_md 2.0.8-8.module+el8.4.0+23842+00253415.1, httpd 2.4.37-39.module+el8.4.0+24495+1afced82.12, mod_http2 1.15.7-3.module+el8.4.0+24495+1afced82.5, mod_ssl 2.4.37-39.module+el8.4.0+24495+1afced82.12, mod_ldap 2.4.37-39.module+el8.4.0+24495+1afced82.12, httpd-tools 2.4.37-39.module+el8.4.0+24495+1afced82.12, +4 more
    fixed: vendor fix RHSA-2026:36846
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) mod_md 2.0.8-8.module+el8.6.0+23843+c27a5dc4.1, httpd 2.4.37-47.module+el8.6.0+24496+af8fe930.13, mod_http2 1.15.7-5.module+el8.6.0+24496+af8fe930.5, mod_ssl 2.4.37-47.module+el8.6.0+24496+af8fe930.13, mod_ldap 2.4.37-47.module+el8.6.0+24496+af8fe930.13, httpd-tools 2.4.37-47.module+el8.6.0+24496+af8fe930.13, +4 more
    fixed: vendor fix RHSA-2026:36831
  • Red Hat Enterprise Linux AppStream TUS (v.8.8) mod_md 2.0.8-8.module+el8.8.0+23840+d7e7db80.1, httpd 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, mod_http2 1.15.7-8.module+el8.8.0+24497+e470c0e2.7, mod_ssl 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, mod_ldap 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, httpd-tools 2.4.37-56.module+el8.8.0+24497+e470c0e2.12, +4 more
    fixed: vendor fix RHSA-2026:36373
  • Red Hat Enterprise Linux Server (v. 7 ELS) httpd 2.4.6-99.el7_9.8 Red Hat Enterprise Linux Server Optional (v. 7 ELS) httpd-debuginfo 2.4.6-99.el7_9.8
    fixed: vendor fix RHSA-2026:92590
  • Red Hat JBoss Core Services 2.4.62.SP4
    fixed: vendor fix RHSA-2026:27201
  • Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd 2.4.62-13.el7jbcs, jbcs-httpd24-mod_ssl 2.4.62-13.el7jbcs, jbcs-httpd24-mod_ldap 2.4.62-13.el7jbcs, jbcs-httpd24-httpd-tools 2.4.62-13.el7jbcs, jbcs-httpd24-mod_session 2.4.62-13.el7jbcs, jbcs-httpd24-httpd-manual 2.4.62-13.el7jbcs, +2 more Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd 2.4.62-13.el8jbcs, jbcs-httpd24-mod_ssl 2.4.62-13.el8jbcs, jbcs-httpd24-mod_ldap 2.4.62-13.el8jbcs, jbcs-httpd24-httpd-tools 2.4.62-13.el8jbcs, jbcs-httpd24-mod_session 2.4.62-13.el8jbcs, jbcs-httpd24-httpd-manual 2.4.62-13.el8jbcs, +2 more
    fixed: vendor fix RHSA-2026:27200
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) httpd 2.4.53-11.el9_2.15, mod_lua 2.4.53-11.el9_2.15, mod_ssl 2.4.53-11.el9_2.15, mod_ldap 2.4.53-11.el9_2.15, httpd-tools 2.4.53-11.el9_2.15, mod_session 2.4.53-11.el9_2.15, +3 more Red Hat Enterprise Linux AppStream E4S (v.9.4) httpd 2.4.57-11.el9_4.5, mod_lua 2.4.57-11.el9_4.5, mod_ssl 2.4.57-11.el9_4.5, mod_ldap 2.4.57-11.el9_4.5, httpd-tools 2.4.57-11.el9_4.5, mod_session 2.4.57-11.el9_4.5, +3 more Red Hat Enterprise Linux Server (v. 7 ELS) mod_ssl 2.4.6-99.el7_9.8, httpd-tools 2.4.6-99.el7_9.8, mod_session 2.4.6-99.el7_9.8, httpd-manual 2.4.6-99.el7_9.8 Red Hat Enterprise Linux Server Optional (v. 7 ELS) mod_ldap 2.4.6-99.el7_9.8, mod_proxy_html 2.4.6-99.el7_9.8 Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-mod_md 2.4.28-16.el7jbcs, jbcs-httpd24-nghttp2 1.64.0-3.el7jbcs, jbcs-httpd24-mod_http2 2.0.29-10.el7jbcs, jbcs-httpd24-mod_security 2.9.6-16.el7jbcs, jbcs-httpd24-mod_jk 1.2.50-14.redhat_1.el7jbcs, jbcs-httpd24-mod_proxy_cluster 1.3.22-9.el7jbcs, +1 more Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-mod_md 2.4.28-16.el8jbcs, jbcs-httpd24-nghttp2 1.64.0-3.el8jbcs, jbcs-httpd24-mod_http2 2.0.29-10.el8jbcs, jbcs-httpd24-mod_security 2.9.6-16.el8jbcs, jbcs-httpd24-mod_jk 1.2.50-14.redhat_1.el8jbcs, jbcs-httpd24-mod_proxy_cluster 1.3.22-9.el8jbcs, +1 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
total
Assessed
6 mo ago

Exploit prediction

1.38% chance of exploitation in the next 30 days, higher than 72% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADP 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
OSV 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
bitnami apache
<2.4.67
2.4.67

Affected products

  • Apache Software Foundation Apache HTTP Server
  • Red Hat JBoss Core Services for RHEL 8
  • Red Hat JBoss Core Services on RHEL 7
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  • Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
  • Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support
  • Red Hat Red Hat JBoss Core Services 2.4.62.SP4
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.