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OpenAdvisories

Description

Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)
processes attacker-supplied CMS data, an attacker-chosen stream-mode KEK
cipher can trigger a heap out-of-bounds read in kek_unwrap_key().

Impact summary: A heap buffer over-read may trigger a crash which leads to
Denial of Service for an application if the input buffer ends at a memory
page boundary and the following page is unmapped. There is no information
disclosure as the over-read bytes are not revealed to the attacker.

The key unwrapping function performs a check-byte test as specified in the
RFC that reads 7 bytes from a heap allocation that is based on the wrapped
key length from the message. There is a minimum length check based on the
block length of the wrapping cipher. However the cipher is selected from
an OID carried in the attacker's PWRI keyEncryptionAlgorithm with no
requirement that the cipher be a block cipher. When an attacker selects
a stream-mode cipher the guard will be ineffective and the allocated buffer
containing the unwrapped key can be too small to fit the check-bytes
specified in the RFC and a buffer over-read can happen.

Applications calling CMS_decrypt() or CMS_decrypt_set1_password()
(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS
data are vulnerable to this issue. No password knowledge is required: the
over-read happens during the unwrap attempt before any authentication
succeeds.

The over-read is limited to a few bytes and is not written to output, so
there is no information disclosure. Triggering a crash requires the
allocation to border unmapped memory, which is unlikely with the normal
allocator.

The FIPS modules are not affected by this issue.

Affected products

VendorProductAffectedFixed
OpenSSL OpenSSL 4.0.0 – < 4.0.1, 3.6.0 – < 3.6.3, 3.5.0 – < 3.5.7, 3.4.0 – < 3.4.6, 3.0.0 – < 3.0.21, 1.1.1 – < 1.1.1zh, 1.0.2 – < 1.0.2zq 4.0.1

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 openssl 3.6.3-1 —
Debian 13 openssl 3.5.6-1~deb13u2 —
Debian 12 openssl 3.0.20-1~deb12u2 —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 edk2 +1 No fix yet —
Ubuntu 26.04 LTS edk2 +1 No fix yet —
Ubuntu 26.04 LTS openssl 3.5.5-1ubuntu3.2 —
Ubuntu 25.10 edk2 No fix yet —
Ubuntu 25.10 openssl 3.5.3-1ubuntu3.4 —
Ubuntu 24.04 LTS edk2 No fix yet —
Ubuntu 24.04 LTS openssl 3.0.13-0ubuntu3.11 —
Ubuntu 22.04 LTS edk2 No fix yet —
Ubuntu 22.04 LTS openssl 3.0.2-0ubuntu1.25 —
Show 14 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu Pro FIPS 20.04 LTS openssl No fix yet —
Ubuntu Pro FIPS 18.04 LTS openssl No fix yet —
Ubuntu Pro FIPS 16.04 LTS openssl No fix yet —
Ubuntu Pro FIPS-updates 24.04 LTS openssl-fips 3.0.13-0ubuntu3.12+Fips1 —
Ubuntu Pro FIPS-updates 22.04 LTS openssl 3.0.2-0ubuntu1.25+Fips1 —
Ubuntu Pro FIPS-updates 22.04 LTS openssl-fips No fix yet —
Ubuntu Pro FIPS-updates 20.04 LTS openssl 1.1.1f-1ubuntu2.fips.24.4 —
Ubuntu Pro FIPS-updates 18.04 LTS openssl 1.1.1-1ubuntu2.fips.2.1~18.04.23.9 —
Ubuntu Pro FIPS-updates 16.04 LTS openssl No fix yet —
Ubuntu Pro FIPS-preview 22.04 LTS openssl +1 No fix yet —
Ubuntu Pro 22.04 LTS nodejs No fix yet —
Ubuntu Pro 20.04 LTS edk2 No fix yet —
Ubuntu Pro 20.04 LTS openssl 1.1.1f-1ubuntu2.24+esm4 —
Ubuntu Pro 18.04 LTS edk2 +1 No fix yet —
Ubuntu Pro 18.04 LTS openssl 1.1.1-1ubuntu2.1~18.04.23+esm9 —
Ubuntu Pro 18.04 LTS openssl1.0 1.0.2n-1ubuntu5.13+esm5 —
Ubuntu Pro 16.04 LTS edk2 +1 No fix yet —
Ubuntu Pro 16.04 LTS openssl 1.0.2g-1ubuntu4.20+esm16 —
Ubuntu Pro 14.04 LTS openssl 1.0.1f-1ubuntu2.27+esm14 —
ReleasePackageFixed inAdvisory
RHEL 10 openssl +3 1:3.5.5-4.el10_2 RHSA-2026:25237
RHEL 9 openssl +3 1:3.5.5-4.el9_8 RHSA-2026:25239
Show 1 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Red Hat Hardened Images 1 bootupd +1 0.3.2-1.hum1 RHSA-2026:67551
Red Hat Hardened Images 1 chunkah 0.6.0-3.hum1 RHSA-2026:42825
Red Hat Hardened Images 1 openssl +10 3.5.8-0.1.hum1 RHSA-2026:59641, RHSA-2026:59635
Red Hat Hardened Images 1 python-cryptography +1 50.0.0-1.hum1 RHSA-2026:55543
Red Hat Hardened Images 1 ruby3.3 +5 3.3.10-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 ruby3.4 +5 3.4.10-31.7.hum1 RHSA-2026:62790
Red Hat Hardened Images 1 ruby4.0 +5 4.0.6-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem3.3-bigdecimal 3.1.5-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-bundler 2.5.22-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-devel +1 3.5.22-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-io-console 0.7.1-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-irb 1.13.1-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-json 2.7.2-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-minitest 5.20.0-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-power_assert 2.0.3-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-psych 5.1.2-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-racc 1.7.3-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-rake 13.1.0-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-rbs 3.4.0-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-rdoc 6.6.3.1-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-rexml 3.4.4-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-rss 0.3.1-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-test-unit 3.6.1-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem3.3-typeprof 0.21.9-23.6.hum1 RHSA-2026:62562
Red Hat Hardened Images 1 rubygem4.0-bigdecimal 4.0.1-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-devel +2 4.0.16-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-io-console 0.8.2-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-irb 1.16.0-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-json 2.18.0-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-minitest 6.0.0-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-power_assert 3.0.1-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-psych 5.3.1-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-racc 1.8.1-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-rake 13.3.1-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-rbs 3.10.0-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-rdoc 7.0.4-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-rexml 3.4.4-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-rss 0.3.2-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-test-unit 3.7.5-37.3.hum1 RHSA-2026:62563
Red Hat Hardened Images 1 rubygem4.0-typeprof 0.31.1-37.3.hum1 RHSA-2026:62563

AlmaLinux

Errata ↗
ReleasePackageFixed inAdvisory
AlmaLinux 10 openssl +3 1:3.5.5-4.el10_2.alma.1 ALSA-2026:25237
AlmaLinux 9 openssl +3 1:3.5.5-4.el9_8 ALSA-2026:25239

Rocky Linux

Errata ↗
ReleasePackageFixed inAdvisory
Rocky Linux 10 openssl 1:3.5.5-4.el10_2 RLSA-2026:25237
Rocky Linux 9 openssl 1:3.5.5-4.el9_8 RLSA-2026:25239
ReleasePackageFixed inAdvisory
SLES 15 SP7 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES 15 SP7 openssl-1_1 1.1.1w-150700.11.22.1 SUSE-SU-2026:2392-1
SLES 15 SP7 openssl-3 3.2.3-150700.5.36.1 SUSE-SU-2026:2648-1
SLES 15 SP6 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES 15 SP6 openssl-1_1 1.1.1w-150600.5.32.1 SUSE-SU-2026:2404-1
SLES 15 SP6 openssl-3 3.1.4-150600.5.53.1 SUSE-SU-2026:2393-1
SLES 15 SP5 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES 15 SP5 openssl-1_1 1.1.1l-150500.17.57.2 SUSE-SU-2026:2405-1
SLES 15 SP5 openssl-3 3.0.8-150500.5.66.1 SUSE-SU-2026:2397-1
SLES 15 SP4 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES 15 SP4 openssl-1_1 1.1.1l-150400.7.96.2 SUSE-SU-2026:2614-1
SLES 15 SP4 openssl-3 3.0.8-150400.4.87.1 SUSE-SU-2026:2598-1
SLES 12 SP5 openssl-1_0_0 1.0.2p-3.109.1 SUSE-SU-2026:2396-1
SLES 12 SP5 openssl-1_1 1.1.1d-2.131.1 SUSE-SU-2026:2403-1
Show 13 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 openssl-3 3.5.0-160000.8.1 SUSE-SU-2026:22315-1
SLES for SAP 15 SP6 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES for SAP 15 SP6 openssl-1_1 1.1.1w-150600.5.32.1 SUSE-SU-2026:2404-1
SLES for SAP 15 SP6 openssl-3 3.1.4-150600.5.53.1 SUSE-SU-2026:2393-1
SLES for SAP 15 SP5 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES for SAP 15 SP5 openssl-1_1 1.1.1l-150500.17.57.2 SUSE-SU-2026:2405-1
SLES for SAP 15 SP5 openssl-3 3.0.8-150500.5.66.1 SUSE-SU-2026:2397-1
SLES for SAP 15 SP4 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLES for SAP 15 SP4 openssl-1_1 1.1.1l-150400.7.96.2 SUSE-SU-2026:2614-1
SLES for SAP 15 SP4 openssl-3 3.0.8-150400.4.87.1 SUSE-SU-2026:2598-1
SLES 16.0 openssl-3 3.5.0-160000.8.1 SUSE-SU-2026:22315-1
SLE Micro 6.2 openssl-3 3.5.0-160000.8.1 SUSE-SU-2026:22251-1
SLE Micro 6.1 openssl-3 3.1.4-slfo.1.1_10.1 SUSE-SU-2026:22132-1
SLE Micro 6.0 openssl-3 3.1.4-14.1 SUSE-SU-2026:22100-1
SLE Micro 5.5 openssl-1_1 1.1.1l-150500.17.57.2 SUSE-SU-2026:2405-1
SLE Micro 5.4 openssl-1_1 1.1.1l-150400.7.96.2 SUSE-SU-2026:2614-1
SLE Micro 5.4 openssl-3 3.0.8-150400.4.87.1 SUSE-SU-2026:2598-1
SLE Micro 5.3 openssl-1_1 1.1.1l-150400.7.96.2 SUSE-SU-2026:2614-1
SLE Micro 5.3 openssl-3 3.0.8-150400.4.87.1 SUSE-SU-2026:2598-1
SLE HPC 15 SP5 openssl-1_1 1.1.1l-150500.17.57.2 SUSE-SU-2026:2405-1
SLE HPC 15 SP5 openssl-3 3.0.8-150500.5.66.1 SUSE-SU-2026:2397-1
SLE HPC 15 SP4 openssl-1_0_0 1.0.2p-150000.3.108.1 SUSE-SU-2026:2399-1
SLE HPC 15 SP4 openssl-1_1 1.1.1l-150400.7.96.2 SUSE-SU-2026:2614-1
SLE HPC 15 SP4 openssl-3 3.0.8-150400.4.87.1 SUSE-SU-2026:2598-1
ReleasePackageFixed inAdvisory
openSUSE Tumbleweed openssl-3 3.5.3-6.1 openSUSE-SU-2026:11023-1
openSUSE Leap 16.0 openssl-3 3.5.0-160000.8.1 openSUSE-SU-2026:21005-1
ReleasePackageFixed inAdvisory
Alpine v3.24 openssl 3.5.7-r0 —
Alpine v3.23 openssl 3.5.7-r0 —
Alpine v3.22 openssl 3.5.7-r0 —
Alpine v3.21 openssl 3.3.7-r1 —

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 openssl +5 1:3.5.5-1.amzn2023.0.5 ALAS2023-2026-1853
Amazon Linux 2 edk2-ovmf +3 20240813-312.amzn2 ALAS2-2026-3363
Amazon Linux 2 openssl +4 1:1.0.2k-24.amzn2.0.21 ALAS2-2026-3365
Amazon Linux 2 openssl11 +3 1:1.1.1zh-1.amzn2.0.1 ALAS2-2026-3364

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 edk2 20240524git3e722403cd16-18 —
Azure Linux 3 openssl 3.3.7-3 —
Azure Linux 3 openssl-fips-provider No fix yet —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 10 openssl +3 1:3.5.5-5.0.1.el10_2 ELSA-2026-25237
Oracle Linux 9 openssl +3 1:3.5.5-4.0.1.el9_8 ELSA-2026-50379, ELSA-2026-25239

Wolfi

ReleasePackageFixed inAdvisory
Wolfi rolling openssl +1 3.6.3-r0 —
Wolfi rolling openssl-4.0 +2 4.0.1-r0 —

Advisories 45

References