SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-3657

Due to inadequate handling of extremely large (>=2GiB) IMAP literals, malicious or compromised IMAP servers, and hypothetically even external email senders, could cause several different buffer overflows, which could conceivably be exploited for remote…

CRITICAL 9.8EPSS 3.46%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (3.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in mbsync versions prior to 1.4.4. Due to inadequate handling of extremely large (>=2GiB) IMAP literals, malicious or compromised IMAP servers, and hypothetically even external email senders, could cause several different buffer overflows, which could conceivably be exploited for remote code execution.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
3.46% probability · 88th percentile
CISA KEV
Not listed
Weakness
CWE-119
Affected
isync project/isync · fedoraproject/fedora · redhat/enterprise linux · debian/debian linux
Source
patrick@puiterwijk.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.