Is CVE-2026-65626 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-65626 being exploited in the wild.

How severe is CVE-2026-65626?

Informational severity, published 26 October 2026.

Is there a fix for CVE-2026-65626?

Yes: fixed in 1.11.13. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-65626 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-65626?

Check whether you run JOSE 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.

CVE-2026-65626: jose RSAES-PKCS1-v1_5 Bleichenbacher padding oracle

CVE-2026-65626 · Severity: info · Published 2026-10-26

The jose Erlang library implements RSA decryption using a vulnerable algorithm that leaks information about whether padding is valid, allowing attackers to decrypt messages without the private key. An attacker who can send encrypted data to a decryption endpoint can recover sensitive keys and encrypted content through thousands of carefully crafted queries, potentially exposing encrypted communications or enabling signature forgery.

Technologies: JOSE. Vendors: Jose.

Quick answers

Is CVE-2026-65626 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-65626 being exploited in the wild.
How severe is CVE-2026-65626?: Informational severity, published 26 October 2026.
Which products and versions are affected?: JOSE 1.3.0 to before 1.11.13.
Is there a fix for CVE-2026-65626?: Yes: fixed in 1.11.13. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-65626 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-65626?: Check whether you run JOSE 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

Fixed in: 1.11.13

Technical details

The vulnerable eme_pkcs1_decode/2 function in jose_jwa_pkcs1 returns distinct error responses for valid versus invalid PKCS#1 v1.5 padding, creating a padding oracle. Combined with unblinded RSA decryption in dp/2, this leaks both a one-bit padding-conformance signal and timing information. An unauthenticated attacker with network access to RSA1_5 JWE decryption endpoints can exploit this through chosen-ciphertext attacks requiring 10^4 to 10^6 queries to recover plaintext.

Affected products

jose jose 1.3.0 to before 1.11.13

Timeline

2026-10-26: disclosed

References

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