How severe is CVE-2021-32055?

CVE-2021-32055 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2021-32055 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32055?

CVE-2021-32055 primarily affects Mutt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-32055?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-32055 published?

CVE-2021-32055 was published on 2021-05-05 and last updated on 2026-06-17.

CVE-2021-32055

CVE-2021-32055 is a critical-severity vulnerability in Mutt with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 5.8
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Mutt
Published: 2021-05-05
Last modified: 2026-06-17

Description

Mutt 1.11.0 through 2.0.x before 2.0.7 (and NeoMutt 2019-10-25 through 2021-05-04) has a $imap_qresync issue in which imap/util.c has an out-of-bounds read in situations where an IMAP sequence set ends with a comma. NOTE: the $imap_qresync setting for QRESYNC is not enabled by default.

Frequently asked questions

What is CVE-2021-32055?: Mutt 1.11.0 through 2.0.x before 2.0.7 (and NeoMutt 2019-10-25 through 2021-05-04) has a $imap_qresync issue in which imap/util.c has an out-of-bounds read in situations where an IMAP sequence set ends with a comma. NOTE: the $imap_qresync setting for QRESYNC is not enabled by default.
How severe is CVE-2021-32055?: CVE-2021-32055 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2021-32055 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32055?: CVE-2021-32055 primarily affects Mutt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-32055?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-32055 published?: CVE-2021-32055 was published on 2021-05-05 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:mutt:mutt:*:*:*:*:*:*:*:*
cpe:2.3:a:neomutt:neomutt:*:*:*:*:*:*:*:*

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