CVE-2026-115559

Publication date 12 November 2026

Last updated 13 November 2026


Ubuntu priority

Description

IMAP4.starttls() wraps the socket in TLS but leaves self._readbuf, imaplib's own read-ahead buffer, untouched. Any plaintext bytes that arrived in the same recv() as the tagged OK to STARTTLS are returned by readline() after the handshake, so the client treats them as the first responses on the protected channel. A network attacker who cannot break TLS can append forged lines after the server's OK, let the handshake complete with the real server and a valid certificate, and have the client accept the forged CAPABILITY and the forged tagged completion of the next command. This is the STARTTLS command/response injection class of CVE-2011-0411.

Status

Package Ubuntu Release Status
python2.7 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
python3.4 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
14.04 LTS trusty
Needs evaluation
python3.5 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
python3.6 26.10 stonking Not in release
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
python3.7 26.10 stonking Not in release
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
python3.8 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
python3.9 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Needs evaluation
python3.10 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
python3.11 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
python3.12 26.10 stonking Not in release
26.04 LTS resolute Not in release
24.04 LTS noble
Needs evaluation
22.04 LTS jammy Not in release
python3.14 26.10 stonking
Needs evaluation
26.04 LTS resolute
Needs evaluation
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Severity score breakdown

CVSS version: CVSS v4.0

Base score 6.3 · Medium

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N


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