CVE-2026-73209

MediumCVSS 6.5

Published: 28/08/2026(UTC)Updated: 28/08/2026(UTC)Translated: 28/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.32%

24th percentile - higher than 24% of all known CVEs

Summary

An attacker that has valid credentials can send crafted compressed data that causes the affected process to exhaust its stack and crash. The affected process is terminated, which can cause degradation or denial of service for IMAP. Update to non-vulnerable version. No publicly available exploits are known.

Risk Assessment

An attacker with IMAP access can cause a process crash, leading to unavailability of the mail service.

Recommendation

Update the software to a non-vulnerable version that includes a fix for processing compressed data.

Other vulnerabilities in IMAP

CVE-2026-40203Low
When IMAP compression is enabled, the same compression state is reused across responses in a session, so response sizes depend on both attacker-supplied mail and other mail in the same mailbox. An attacker that can send mail to a user and can also observe the sizes of that user's IMAP traffic can confirm whether the body of a small message matches a guessed text. Recovery of arbitrary unknown content was not demonstrated, but the attack can disclose whether a secret-like message body matches a candidate.

Original NVD description (English source)