CVE-2021-29952

mediumpriority · track · 30EPSS 0.007 · 54 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.74% (54th) EPSS

CVSS 5.1 · medium

Is it mine?

14 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

When Web Render components were destructed, a race condition could have caused undefined behavior, and we presume that with enough effort may have been exploitable to run arbitrary code. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.1–8.8

v2.05.1mediumAV:N/AC:H/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 4.9 · impact 6.4

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.6 · impact 5.9

v3.18.8highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.16.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-362USprimaryCWE-362US

affected products (14)

Products and version ranges known to be affected.

Mozilla Firefoxunspecified → 88.0.1enisa_euvdEU
Mozilla Firefox for Androidunspecified → 88.1.3enisa_euvdEU
Canonical Ltd. Ubuntu≤ 21.04fstec_bduRU
Canonical Ltd. Ubuntu≤ 20.10fstec_bduRU
Canonical Ltd. Ubuntu≤ 20.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 18.04 LTSfstec_bduRU
Mozilla Corp. Firefox≤ 88.1.3fstec_bduRU
Mozilla Corp. Firefox≤ 88.0.1fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.4.2fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.2 Муромfstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
mozilla firefox< 88.0.1nvdUScpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
mozilla firefox< 88.1.3nvdUScpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-06-24modified 2026-06-17

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+4148 more

references (13)

External citations — patches, advisories, analysis.

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