CVE-2021-29953

mediumpriority · track · 24EPSS 0.006 · 51 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.65% (51st) EPSS

CVSS 4.3 · medium

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.

cvss

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

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.16.1mediumAV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79US

affected products (5)

Products and version ranges known to be affected.

Mozilla Firefoxunspecified → 88.0.1enisa_euvdEU
Mozilla Firefox for Androidunspecified → 88.1.3enisa_euvdEU
Mozilla Corp. Firefox≤ 88.1.3fstec_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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+53060 more

references (11)

External citations — patches, advisories, analysis.

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