CVE-2026-63072

Aliases:DEBIAN-CVE-2026-63072UBUNTU-CVE-2026-63072ALPINE-CVE-2026-63072CGA-2mxf-cf8j-q96pCGA-2x9r-mjwr-v93pCGA-482g-x7h5-jf63CGA-57fq-26gg-3gpmCGA-6c47-7f3p-7j24CGA-7q5m-9c7f-5x2cCGA-943v-9fp8-m92hCGA-9ffj-jm47-fmq5CGA-cp9q-7p7g-2q2pCGA-f56p-c55w-mrr5CGA-j9wm-9j95-3c3rCGA-r988-5c7x-jf3mCGA-wm6v-gqmm-w657CGA-xp2v-6w2p-q97jSUSE-SU-2026:4034-1SUSE-SU-2026:4036-1SUSE-SU-2026:4037-1SUSE-SU-2026:4042-1
Advisory lineage Upstream: 0 Downstream: 24
Analyzed
Published: 25 Aug 2026, 12:59
Last modified:25 Aug 2026, 14:29

Vulnerability Summary

Overall Risk (default)
medium
30/100
CVSS Score
7.5 HIGH
v3.1 (cve.org)
EPSS Score
0.68% LOW
1% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

25 Aug 2026, 12:59
Published
Vulnerability first disclosed
25 Aug 2026, 14:29
Last Modified
Vulnerability information updated

Description

Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports, causing an 8-byte out-of-bounds heap write. Impact summary: An attacker who supplies a crafted CMS message can trigger a deterministic 8-byte out-of-bounds heap write when the victim decrypts it with CMS_decrypt(), corrupting the heap and typically resulting in a Denial of Service. CWE: CWE-787: Out-of-bounds Write Description: The key-wrap OID is potentially attacker-controlled on the wire. CMS unwrapping allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers. An attacker can take a legitimate message and change a single OID byte to select the padded variant while leaving the message otherwise valid. Since the unwrap key is derived from the recipient's private operation (ECDH key agreement or ML-KEM decapsulation), the RFC 5649 integrity check cannot pass, and the decryption fails with integrity failure. The write is a fixed-size (8-byte), fixed-value (zero) heap overflow immediately past the allocation, requires no special configuration, and is reachable from the public CMS_decrypt() function. The consequence is a heap corruption leading to a Denial of Service. The fix in the CMS code sizes the unwrap output buffer for the worst case so a failed unwrap cannot write past the allocation. FIPS impact: no As the CMS code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.

CVSS Metrics

  • v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.68%• Percentile: 51%

Techniques & Countermeasures

  • CWE-787•Out-of-bounds Write

    The product writes data past the end, or before the beginning, of the intended buffer.

Affected Systems

  • alpine•openssl

    < 3.5.8-r0 | < 3.5.8-r0 | < 3.5.8-r0 | ≥ 3.0.0, < 3.3.7-r1 | ≥ 3.0.0, < 3.5.8-r0 | ≥ 3.0.0, < 3.5.8-r0 | ≥ 3.0.0, < 3.5.8-r0

  • chainguard•eco-python-openssl-4

    all | < 4.0.2-r0

  • chainguard•eco-python-openssl-4-pyca

    all | < 4.0.2-r0

  • chainguard•eco-python-openssl-4-pyca-dev

    all | < 4.0.2-r0

  • chainguard•openssl-provider-fips-3.4.0

    all | < 0

  • chainguard•openssl-provider-fips-3.4.0-dbg

    all

  • chainguard•openssl-provider-fips-3.6.0

    all

  • chainguard•openssl-provider-fips-3.6.0-dbg

    all | < 0

  • debian•openssl

    all | all | all | < 3.5.7-1~deb13u2 | < 3.6.4-1

  • ubuntu•edk2

    all | all | all | all | all

  • ubuntu•edk2-hwe

    all

  • ubuntu•nodejs

    all

  • ubuntu•openssl

    < 1.0.1f-1ubuntu2.27+esm16 | < 1.0.2g-1ubuntu4.20+esm18 | all | < 1.1.1-1ubuntu2.1~18.04.23+esm10 | < 1.1.1f-1ubuntu2.24+esm5 | < 3.0.2-0ubuntu1.29 | < 3.0.2-0ubuntu1.29+Fips1 | < 3.0.13-0ubuntu3.15 | < 3.5.5-1ubuntu3.4

  • ubuntu•openssl-fips

    all | < 3.0.13-0ubuntu3.15+Fips1

  • ubuntu•openssl1.0

    < 1.0.2n-1ubuntu5.13+esm6

  • openssl•openssl

    ≥ 1.1.1, < 1.1.1zi | ≥ 3.0.0, < 3.0.22 | ≥ 3.4.0, < 3.4.7 | ≥ 3.5.0, < 3.5.8 | ≥ 3.6.0, < 3.6.4 | ≥ 4.0.0, < 4.0.2

  • suse•openssl-1_1-livepatches&distro=SUSE Linux Enterprise Live Patching 15 SP4

    < 0.8-150400.3.26.1

  • suse•openssl-1_1-livepatches&distro=SUSE Linux Enterprise Live Patching 15 SP5

    < 0.8-150500.6.17.1

  • suse•openssl-1_1-livepatches&distro=SUSE Linux Enterprise Live Patching 15 SP6

    < 0.8-150600.11.9.1

  • suse•openssl-1_1-livepatches&distro=SUSE Linux Enterprise Live Patching 15 SP7

    < 0.8-150700.13.12.1

References (23)