Quick answers
- Is CVE-2026-107496 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-107496 being exploited in the wild.
- How severe is CVE-2026-107496?
- Informational severity, published 10 November 2026.
- Which products and versions are affected?
- OpenSSL 3.0, 3.5, 4.0, 4.1 (when enable-ec_explicit_curves is configured).
- Is there a fix for CVE-2026-107496?
- No fixed version is recorded yet. Do not encrypt CMS messages to certificates with attacker-controlled EC parameters, or restrict the use of CMS encryption to trusted recipient certificates only. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-107496 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-107496?
- Check whether you run OpenSSL at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
Do not encrypt CMS messages to certificates with attacker-controlled EC parameters, or restrict the use of CMS encryption to trusted recipient certificates only.
Technical details
CMS_encrypt() and CMS_encrypt_ex() fail to validate EC group order and enter an infinite loop when attempting to generate an ephemeral key for a group with order 1, since no nonzero scalar can be generated. The vulnerability requires an attacker-controlled recipient certificate and affects only applications that explicitly call these functions; normal TLS/QUIC usage is not impacted. The fix makes key generation fail cleanly instead of retrying indefinitely.
Affected products
- OpenSSL OpenSSL 3.0, 3.5, 4.0, 4.1 (when enable-ec_explicit_curves is configured)