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Vulnerability record · CVE-2021-29948 · published 24 June 2021

CVE-2021-29948: Mozilla thunderbird race condition vulnerability

Mozilla · Thunderbird

Signatures are written to disk before and read during verification, which might be subject to a race condition when a malicious local process or user is replacing the file. This vulnerability affects Thunderbird < 78.10.

2.5 CVSS 3.1 Low EPSS 0.29% · top 81.0% CWE-362 · Race condition
2.5CVSS 3.1 base score, v2 1.9
0.29%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

Signatures are written to disk before and read during verification, which might be subject to a race condition when a malicious local process or user is replacing the file. This vulnerability affects Thunderbird < 78.10.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://bugzilla.mozilla.org/show_bug.cgi?id=1692899 ExploitPatchVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-14/ Release NotesVendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1692899 ExploitPatchVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-14/ Release NotesVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-29948), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.