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Fencer Vulns
high 7.4

CVE-2025-49812 json

Apache HTTP Server: mod_ssl TLS upgrade attack

published 2025-07-10 15 mo ago modified 2026-09-08 2 mo ago also BIT-apache-2025-49812 , EUVD-2025-21016

cvss
7.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 55%
public exploits
0
none known

Summary

In some mod_ssl configurations on Apache HTTP Server versions through to 2.4.63, an HTTP desynchronisation attack allows a man-in-the-middle attacker to hijack an HTTP session via a TLS upgrade.

Only configurations using "SSLEngine optional" to enable TLS upgrades are affected. Users are recommended to upgrade to version 2.4.64, which removes support for TLS upgrade.

Patch / fix

  • bitnami apache 2.4.64
  • apache http_server 2.4.64
  • apache2 Debian 12 2.4.65-1~deb12u1
  • apache2 Debian 14, Debian 13 2.4.64-1

debian advisories DEBIAN-CVE-2025-49812

  • apache2 Ubuntu 22.04 LTS 2.4.52-1ubuntu4.15
  • apache2 Ubuntu 24.04 LTS 2.4.58-1ubuntu8.7
  • apache2 Ubuntu Pro 14.04 LTS 2.4.7-1ubuntu4.22+esm12
  • apache2 Ubuntu Pro 16.04 LTS 2.4.18-2ubuntu3.17+esm16
  • apache2 Ubuntu Pro 18.04 LTS 2.4.29-1ubuntu4.27+esm6
  • apache2 Ubuntu Pro 20.04 LTS 2.4.41-4ubuntu3.23+esm2

ubuntu advisories UBUNTU-CVE-2025-49812

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

  • httpd RHEL 8 2.4.37-65.module+el8.10.0+23369+11a81384.5
  • mod_md RHEL 8 1:2.0.8-8.module+el8.9.0+19080+567b90f8
  • mod_ssl RHEL 8 1:2.4.37-65.module+el8.10.0+23369+11a81384.5
  • mod_ldap RHEL 8 2.4.37-65.module+el8.10.0+23369+11a81384.5
  • mod_http2 RHEL 8 1.15.7-10.module+el8.10.0+23369+11a81384.4
  • httpd-tools RHEL 8 2.4.37-65.module+el8.10.0+23369+11a81384.5
  • mod_session RHEL 8 2.4.37-65.module+el8.10.0+23369+11a81384.5
  • httpd-manual RHEL 8 2.4.37-65.module+el8.10.0+23369+11a81384.5

red hat advisories RHSA-2025:15698RHSA-2025:15684RHSA-2025:15619RHSA-2025:15516RHSA-2025:15123RHSA-2025:15095

  • 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 SLE Module for Basesystem 15 SP7 2.4.62-150700.4.3.1
  • apache2-event SLE Module for Package Hub 15 SP7 2.4.62-150700.4.3.1
  • apache2-utils SLE Module for Server Applications 15 SP7 2.4.62-150700.4.3.1
  • apache2-worker SLE Module for Server Applications 15 SP7 2.4.62-150700.4.3.1
  • apache2-prefork SLE Module for Basesystem 15 SP7 2.4.62-150700.4.3.1
  • apache2 SLE Module for Package Hub 15 SP6, SLE Module for Basesystem 15 SP6, openSUSE Leap 15.6 2.4.58-150600.5.35.1
  • apache2-event SLE Module for Package Hub 15 SP6, openSUSE Leap 15.6 2.4.58-150600.5.35.1

suse advisories SUSE-SU-2026:2686-1SUSE-SU-2025:02685-1SUSE-SU-2025:02684-1SUSE-SU-2025:02683-1SUSE-SU-2025:02682-1SUSE-SU-2025:02565-1

  • cyrus-imapd openSUSE Leap 16.0 3.8.6-bp160.1.1
  • cyrus-imapd openSUSE Tumbleweed 3.8.6-1.1
  • apache2 openSUSE Tumbleweed 2.4.64-1.1

opensuse advisories openSUSE-SU-2026:20962-1openSUSE-SU-2025:15369-1openSUSE-SU-2025:15360-1

  • httpd AlmaLinux 8 2.4.37-65.module_el8.10.0+4044+ea5f78b1.5
  • mod_md AlmaLinux 8 1:2.0.8-8.module_el8.6.0+2872+fe0ff7aa
  • mod_md AlmaLinux 8 1:2.0.8-8.module_el8.6.0+3031+fb177b09
  • mod_ssl AlmaLinux 8 1:2.4.37-65.module_el8.10.0+4044+ea5f78b1.5
  • mod_ldap AlmaLinux 8 2.4.37-65.module_el8.10.0+4044+ea5f78b1.5
  • mod_http2 AlmaLinux 8 1.15.7-10.module_el8.10.0+4044+ea5f78b1.4
  • httpd-tools AlmaLinux 8 2.4.37-65.module_el8.10.0+4044+ea5f78b1.5
  • mod_session AlmaLinux 8 2.4.37-65.module_el8.10.0+4044+ea5f78b1.5

almalinux advisories ALSA-2025:15123ALSA-2025:15023ALSA-2025:15095

  • httpd Rocky Linux 9 2.4.62-4.el9_6.4
  • httpd Rocky Linux 10 2.4.63-1.el10_0.2
  • 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+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+1830+22f0c9e0
  • httpd Rocky Linux 8 2.4.37-65.module+el8.10.0+1842+4a9649e8.2
  • mod_md Rocky Linux 8 1:2.0.8-8.module+el8.9.0+1370+89cc8ad5

rocky linux advisories RLSA-2025:15023RLSA-2025:15095RLSA-2025:15123

  • apache2 Alpine 3.24, Alpine 3.23, Alpine 3.22 +3 more 2.4.64-r0

alpine advisories ALPINE-CVE-2025-49812

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

  • httpd CBL-Mariner 2.0, Azure Linux 3.0 2.4.64-1

azure linux advisories AZL-65097AZL-65112

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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-2025-49812 updated cvss 7.5

httpd: HTTP Session Hijack via a TLS upgrade

  • Red Hat Enterprise Linux AppStream (v. 8) mod_md 2.0.8-8.module+el8.9.0+19080+567b90f8, httpd 2.4.37-65.module+el8.10.0+23369+11a81384.5, mod_ssl 2.4.37-65.module+el8.10.0+23369+11a81384.5, mod_ldap 2.4.37-65.module+el8.10.0+23369+11a81384.5, mod_http2 1.15.7-10.module+el8.10.0+23369+11a81384.4, httpd-tools 2.4.37-65.module+el8.10.0+23369+11a81384.5, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15123
  • Red Hat Enterprise Linux AppStream (v. 9) httpd 2.4.62-4.el9_6.4, mod_lua 2.4.62-4.el9_6.4, mod_ssl 2.4.62-4.el9_6.4, mod_ldap 2.4.62-4.el9_6.4, httpd-core 2.4.62-4.el9_6.4, httpd-tools 2.4.62-4.el9_6.4, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15023
  • Red Hat Enterprise Linux AppStream (v. 10) httpd 2.4.63-1.el10_0.2, mod_lua 2.4.63-1.el10_0.2, mod_ssl 2.4.63-1.el10_0.2, mod_ldap 2.4.63-1.el10_0.2, httpd-core 2.4.63-1.el10_0.2, httpd-tools 2.4.63-1.el10_0.2, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15095
  • Red Hat Enterprise Linux AppStream AUS (v. 8.2) mod_md 2.0.8-7.module+el8.2.0+5531+7e4d69a2, httpd 2.4.37-21.module+el8.2.0+23461+1d03af5c.10, mod_http2 1.11.3-3.module+el8.2.0+23461+1d03af5c.5, mod_ssl 2.4.37-21.module+el8.2.0+23461+1d03af5c.10, mod_ldap 2.4.37-21.module+el8.2.0+23461+1d03af5c.10, httpd-tools 2.4.37-21.module+el8.2.0+23461+1d03af5c.10, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15516
  • Red Hat Enterprise Linux AppStream AUS (v.8.4) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, mod_http2 1.15.7-3.module+el8.4.0+23462+1fa78ba3.4, mod_ssl 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, mod_ldap 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, httpd-tools 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15684
  • Red Hat Enterprise Linux AppStream AUS (v.8.6) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_http2 1.15.7-5.module+el8.6.0+23463+5d5709c6.4, mod_ssl 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_ldap 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, httpd-tools 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, +4 more Red Hat Enterprise Linux AppStream E4S (v.8.6) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_http2 1.15.7-5.module+el8.6.0+23463+5d5709c6.4, mod_ssl 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_ldap 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, httpd-tools 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15698
  • Red Hat Enterprise Linux AppStream E4S (v.8.8) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-56.module+el8.8.0+23464+a2e0c444.10, mod_http2 1.15.7-8.module+el8.8.0+23464+a2e0c444.6, mod_ssl 2.4.37-56.module+el8.8.0+23464+a2e0c444.10, mod_ldap 2.4.37-56.module+el8.8.0+23464+a2e0c444.10, httpd-tools 2.4.37-56.module+el8.8.0+23464+a2e0c444.10, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15619
  • Red Hat Enterprise Linux AppStream E4S (v.9.0) httpd 2.4.51-7.el9_0.10, mod_lua 2.4.51-7.el9_0.10, mod_ssl 2.4.51-7.el9_0.10, mod_ldap 2.4.51-7.el9_0.10, httpd-tools 2.4.51-7.el9_0.10, mod_session 2.4.51-7.el9_0.10, +3 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14901
show 11 more
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) httpd 2.4.53-11.el9_2.13, mod_lua 2.4.53-11.el9_2.13, mod_ssl 2.4.53-11.el9_2.13, mod_ldap 2.4.53-11.el9_2.13, httpd-core 2.4.53-11.el9_2.13, httpd-tools 2.4.53-11.el9_2.13, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14902
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) httpd 2.4.57-11.el9_4.3, mod_lua 2.4.57-11.el9_4.3, mod_ssl 2.4.57-11.el9_4.3, mod_ldap 2.4.57-11.el9_4.3, httpd-core 2.4.57-11.el9_4.3, httpd-tools 2.4.57-11.el9_4.3, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14903
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, mod_http2 1.15.7-3.module+el8.4.0+23462+1fa78ba3.4, mod_ssl 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, mod_ldap 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, httpd-tools 2.4.37-39.module+el8.4.0+23462+1fa78ba3.10, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15684
  • Red Hat Enterprise Linux AppStream TUS (v.8.6) mod_md 2.0.8-8.module+el8.3.0+6814+67d1e611, httpd 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_http2 1.15.7-5.module+el8.6.0+23463+5d5709c6.4, mod_ssl 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, mod_ldap 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, httpd-tools 2.4.37-47.module+el8.6.0+23463+5d5709c6.11, +4 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15698
  • Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) httpd 2.2.15-71.el6_10.1, mod_ssl 2.2.15-71.el6_10.1, httpd-tools 2.2.15-71.el6_10.1, httpd-manual 2.2.15-71.el6_10.1
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:15036
  • Red Hat Enterprise Linux Server (v. 7 ELS) httpd 2.4.6-99.el7_9.6, mod_ssl 2.4.6-99.el7_9.6, httpd-tools 2.4.6-99.el7_9.6, mod_session 2.4.6-99.el7_9.6, httpd-manual 2.4.6-99.el7_9.6
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14997
  • Red Hat Enterprise Linux Server AUS (v. 7.7) httpd 2.4.6-90.el7_7.6, mod_ssl 2.4.6-90.el7_7.6, httpd-tools 2.4.6-90.el7_7.6, mod_session 2.4.6-90.el7_7.6, httpd-manual 2.4.6-90.el7_7.6
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14998
  • Red Hat Enterprise Linux Server Optional (v. 7 ELS) mod_ldap 2.4.6-99.el7_9.6, mod_proxy_html 2.4.6-99.el7_9.6
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14997
  • Red Hat Enterprise Linux Server Optional AUS (v. 7.7) mod_ldap 2.4.6-90.el7_7.6, mod_proxy_html 2.4.6-90.el7_7.6
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:14998
  • Red Hat JBoss Core Services 2.4.62.SP1
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:13681
  • Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd 2.4.62-8.el7jbcs, jbcs-httpd24-mod_md 2.4.28-10.el7jbcs, jbcs-httpd24-mod_ssl 2.4.62-8.el7jbcs, jbcs-httpd24-mod_ldap 2.4.62-8.el7jbcs, jbcs-httpd24-mod_http2 2.0.29-5.el7jbcs, jbcs-httpd24-httpd-tools 2.4.62-8.el7jbcs, +8 more Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd 2.4.62-8.el8jbcs, jbcs-httpd24-mod_md 2.4.28-10.el8jbcs, jbcs-httpd24-mod_ssl 2.4.62-8.el8jbcs, jbcs-httpd24-mod_ldap 2.4.62-8.el8jbcs, jbcs-httpd24-mod_http2 2.0.29-5.el8jbcs, jbcs-httpd24-httpd-tools 2.4.62-8.el8jbcs, +8 more
    fixed: vendor fix “No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.” RHSA-2025:13680

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
no
Technical impact
total
Assessed
15 mo ago

Exploit prediction

0.75% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CNA 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
OSV 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
bitnami apache
<2.4.64
2.4.64

Affected products

  • Apache Software Foundation Apache HTTP Server

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.