CVE-2026-75806

Publication date 29 September 2026

Last updated 30 September 2026

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

5.3 · Medium

Score breakdown

Description

Issue summary: An established DTLS 1.2 association using an AEAD cipher suite can be terminated by a single unauthenticated datagram whose encrypted fragment is shorter than the mandatory explicit IV and authentication tag overhead. Impact summary: An attacker who can send a datagram that is routed to an existing DTLS 1.2 association can tear that association down without knowing any key material. This is a Denial of Service limited to the targeted association. There is no memory safety or confidentiality impact. CWE: CWE-1284: Improper Validation of Specified Quantity in Input Description: In TLS 1.2 and DTLS 1.2 every record protected by an AEAD cipher suite carries an explicit IV followed by the ciphertext and an authentication tag. When decrypting such a record the record layer passed the record length to the cipher implementation before checking that the record was long enough to contain the explicit IV and the tag. For a record shorter than that overhead the cipher implementation rejected the impossible length, and the record layer treated this as an internal failure and raised a fatal internal_error alert instead of treating the record as one that failed authentication. In TLS 1.2 the same record causes a fatal internal_error alert instead of the expected bad_record_mac alert. Since any undecryptable record already terminates a TLS connection, this is a protocol conformance issue rather than a security issue in TLS. The fix validates the record length against the explicit IV and tag length before any AEAD processing, so that TLS reports bad_record_mac and DTLS silently discards the record. FIPS impact: no The affected code is outside the FIPS module boundary.

Read the notes from the security team

Why is this CVE low priority?

OpenSSL developers have rated this issue as being low severity

Learn more about Ubuntu priority

Status

Package Ubuntu Release Status
openssl 26.04 LTS resolute
Fixed 3.5.5-1ubuntu3.6
24.04 LTS noble
Fixed 3.0.13-0ubuntu3.16
22.04 LTS jammy
Fixed 3.0.2-0ubuntu1.30
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
openssl-fips 26.04 LTS resolute 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
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Needs evaluation
nodejs 26.04 LTS resolute
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Not affected
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Not affected
edk2 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
edk2-hwe 26.04 LTS resolute
Needs evaluation
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Notes

mdeslaur

edk2 in jammy embeds OpenSSL 1.1.1j edk2 in noble embeds OpenSSL 3.0.9 edk2 in resolute embeds OpenSSL 3.5.1 edk2 in stonking embeds OpenSSL 3.5.1 nodejs in jammy embeds OpenSSL 1.1.1m 4.0, 3.6, 3.5, 3.4, 3.0 and 1.1.1 are vulnerable

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.3 · Medium

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

References

Related Ubuntu Security Notices (USN)

    • USN-8847-1
    • OpenSSL vulnerabilities
    • 29 September 2026

Other references

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