CVE-2025-13470

Summary

In RNP version 0.18.0 a refactoring regression causes the symmetric session key used for Public-Key Encrypted Session Key (PKESK) packets to be left uninitialized except for zeroing, resulting in it always being an all-zero byte array.

Any data encrypted using public-key encryption in this release can be decrypted trivially by supplying an all-zero session key, fully compromising confidentiality.

The vulnerability affects only public key encryption (PKESK packets).  Passphrase-based encryption (SKESK packets) is not affected.

Root cause: Vulnerable session key buffer used in PKESK packet generation.

The defect was introduced in commit 7bd9a8dc356aae756b40755be76d36205b6b161a where initialization logic inside encrypted_build_skesk() only randomized the key for the SKESK path and omitted it for the PKESK path.

Affected Software

Weaknesses

• CWE-330: CWE-330 Use of Insufficiently Random Values

Workarounds

No workaround.  All PKESK-encrypted ciphertext produced with 0.18.0 is compromised.

ADP Enrichment

CISA ADP Vulnrichment

• SSVC:
• Exploitation: none
  • Automatable: yes
  • Technical Impact: partial

References

• https://github.com/rnpgp/rnp/commit/7bd9a8dc356aae756b40755be76d36205b6b161a
• https://launchpad.net/ubuntu/+source/rnp
• https://aur.archlinux.org/packages/rnp
• https://packages.gentoo.org/packages/dev-util/librnp
• https://bugzilla.redhat.com/show_bug.cgi?id=2415863
• https://access.redhat.com/security/cve/cve-2025-13402
• https://open.ribose.com/advisories/ra-2025-11-20/
• https://github.com/rnpgp/rnp/releases/tag/v0.18.1

• ←Previous
• Next→