CVE-2021-29986

Status: ModifiedHigh (8.1)—

A suspected race condition when calling getaddrinfo led to memory corruption and a potentially exploitable crash. *Note: This issue only affected Linux operating systems. Other operating systems are unaffected.* This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Base score: 8.1

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.26%
Percentile among all scored CVEs: 69
Score date: 10/7/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (3)

Mozilla — Firefox Mozilla — Firefox ESR Mozilla — Thunderbird

CWEs

CWE-362

References

Raw JSON (NVD)

Show

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    },
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    }
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