CVE-2021-29991

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Summary

CVECVE-2021-29991
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-11-03 01:15:00 UTC
Updated2021-11-04 21:01:00 UTC
DescriptionFirefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.

Risk And Classification

Problem Types: CWE-444

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Mozilla Firefox All All All All
Application Mozilla Thunderbird All All All All

References

ReferenceSourceLinkTags
Security Vulnerabilities fixed in Firefox 91.0.1 and Thunderbird 91.0.1 — Mozilla MISC www.mozilla.org
Access Denied MISC bugzilla.mozilla.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 198470 Ubuntu Security Notification for Firefox Vulnerability (USN-5047-1)
  • 198641 Ubuntu Security Notification for Thunderbird Vulnerabilities (USN-5248-1)
  • 296066 Oracle Solaris 11.4 Support Repository Update (SRU) 40.107.3 Missing (CPUOCT2021)
  • 375824 Mozilla Firefox Header Splitting Vulnerability(MFSA2021-37)
  • 375825 Mozilla Thunderbird Header Splitting Vulnerability(MFSA2021-37)
  • 502080 Alpine Linux Security Update for firefox
  • 502381 Alpine Linux Security Update for thunderbird
  • 503632 Alpine Linux Security Update for thunderbird
  • 503634 Alpine Linux Security Update for thunderbird
  • 503650 Alpine Linux Security Update for thunderbird
  • 503669 Alpine Linux Security Update for thunderbird
  • 503851 Alpine Linux Security Update for firefox
  • 506260 Alpine Linux Security Update for thunderbird
  • 751210 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3331-1)
  • 751226 OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:3331-1)
  • 751237 OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:3451-1)
  • 751246 OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:1367-1)
  • 751369 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3191-1)
  • 751542 OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:4150-1)
  • 751566 OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:1635-1)
  • 752111 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2022:1582-1)
  • 752113 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2022:1577-1)
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