CVE-2026-42766

Possible NULL Dereference in Password-Based CMS Decryption

MEDIUM 5.9

At a glance

Source: NVD
EPSS: EPSS 1.06 % · percentile 64 (2026-10-28)
State: PUBLISHED
Published: 2026-06-09 16:03 UTC
Updated: 2026-06-10 07:48 UTC
Assigner: openssl
NVD status: Analyzed

Description

Issue summary: A specially crafted password-encrypted CMS message can trigger a NULL pointer dereference during CMS decryption. Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service. The CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as OPTIONAL in the ASN.1 specification and may therefore be absent in specially crafted inputs. During the password-based CMS decryption the OpenSSL CMS implementation dereferences this field without first checking whether it was present. An attacker who supplies such a CMS message to an application performing password-based CMS decryption can trigger an application crash, leading to a Denial of Service. Applications that process password-encrypted CMS messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Weaknesses (CWE)

CWE-476 — NULL Pointer Dereference

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H	CISA-ADP
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H	NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

European references

ENISA EUVD · EUVD-2026-35483
GCVE · GCVE-0-2026-42766

CERT-FR advisories

CERTFR-2026-AVI-1390 — Multiples vulnérabilités dans Tenable Network Monitor · cert.ssi.gouv.fr
CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-1352 — Multiples vulnérabilités dans Oracle PeopleSoft · cert.ssi.gouv.fr
CERTFR-2026-AVI-1351 — Multiples vulnérabilités dans Oracle MySQL · cert.ssi.gouv.fr
CERTFR-2026-AVI-1249 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-1056 — Multiples vulnérabilités dans les produits Splunk · cert.ssi.gouv.fr
CERTFR-2026-AVI-0933 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
CERTFR-2026-AVI-0914 — Multiples vulnérabilités dans Oracle Database Server · cert.ssi.gouv.fr
CERTFR-2026-AVI-0796 — Multiples vulnérabilités dans Tenable Identity Exposure · cert.ssi.gouv.fr
CERTFR-2026-AVI-0783 — Multiples vulnérabilités dans Microsoft Azure · cert.ssi.gouv.fr
CERTFR-2026-AVI-0782 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
CERTFR-2026-AVI-0717 — Multiples vulnérabilités dans OpenSSL · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 1.0.2 < 1.0.2zq
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 1.1.1 < 1.1.1zh
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 3.0.0 < 3.0.21
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 3.4.0 < 3.4.6
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 3.5.0 < 3.5.7
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* ≥ 3.6.0 < 3.6.3
cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*

Affected products

Product	Versions
OpenSSL · OpenSSL	affected 4.0.0 < 4.0.1 ; affected 3.6.0 < 3.6.3 ; affected 3.5.0 < 3.5.7 ; affected 3.4.0 < 3.4.6 ; affected 3.0.0 < 3.0.21 ; affected 1.1.1 < 1.1.1zh

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD