CVE-2026-45446

Publication date 9 June 2026

Last updated 18 June 2026

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

4.8 · Medium

Score breakdown

Description

Issue summary: The implementations of AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) mishandle the authentication of AAD (Additional Authenticated Data) with an empty ciphertext allowing a forgery of such messages. Impact summary: An attacker can forge empty messages with arbitrary AAD to the victim's application using these ciphers. AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) are nonce-misuse-resistant AEAD modes: they accept a key, nonce, optional AAD (bytes that are authenticated but not encrypted), and plaintext, and produces ciphertext plus a 16-byte tag. On decrypt, `EVP_DecryptFinal_ex()` is documented to return success only if the tag is verified succesfully. In OpenSSL's provider implementation of these ciphers, the expected tag is computed only when decryption function is invoked with non-empty data. If the caller supplies AAD and then calls `EVP_DecryptFinal_ex()` without invocation of the ciphertext update, which can happen when the received ciphertext length is zero, the tag is never recalculated and still holds its all-zeros value. When AES-GCM-SIV is used, an attacker who sends arbitrary AAD, empty ciphertext, and all-zeros tag passes authentication under any key they do not know, single-shot. When AES-SIV is used, for mounting the attack it's necessary for the application to reuse the decryption context without resetting the key. AES-SIV is implemented since OpenSSL 3.0. AES-GCM-SIV is implemented since OpenSSL 3.2. No protocols implemented in OpenSSL itself (TLS/CMS/PKCS7/HPKE/QUIC) support either AES-GCM-SIV or AES-SIV. To mount an attack, the applications must implement their own protocol and use the EVP interface. Also they must skip the ciphertext update when a message with an empty ciphertext arrives. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as these algorithms are not FIPS approved and the affected code is outside the OpenSSL FIPS module boundary.

Read the notes from the security team

Why is this CVE low priority?

OpenSSL developers have rated this as being low severity

Learn more about Ubuntu priority

Status

Package Ubuntu Release Status
edk2 26.04 LTS resolute
Needs evaluation
25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
nodejs 26.04 LTS resolute
Not affected
25.10 questing
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
14.04 LTS trusty
Not affected
openssl 26.04 LTS resolute
Fixed 3.5.5-1ubuntu3.2
25.10 questing
Fixed 3.5.3-1ubuntu3.4
24.04 LTS noble
Fixed 3.0.13-0ubuntu3.11
22.04 LTS jammy
Fixed 3.0.2-0ubuntu1.25
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
openssl-fips 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
openssl1.0 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Not affected

Notes

mdeslaur

edk2 in jammy embeds OpenSSL 1.1.1j edk2 in noble embeds OpenSSL 3.0.9 edk2 in plucky embeds OpenSSL 3.4.0 edk2 in questing embeds OpenSSL 3.4.0 nodejs in jammy embeds OpenSSL 1.1.1m OpenSSL 4.0, 3.6, 3.5, 3.4 and 3.0 (AES-SIV mode only) are vulnerable to this issue.

Severity score breakdown

CVSS version: CVSS v3.0

Base score 4.8 · Medium

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

Related Ubuntu Security Notices (USN)

Other references

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