CVE-2021-38507

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Summary

CVECVE-2021-38507
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-12-08 22:15:00 UTC
Updated2022-12-09 15:54:00 UTC
DescriptionThe Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin with unencrypted connections on port 80. However, if a second encrypted port on the same IP address (e.g. port 8443) did not opt-in to opportunistic encryption; a network attacker could forward a connection from the browser to port 443 to port 8443, causing the browser to treat the content of port 8443 as same-origin with HTTP. This was resolved by disabling the Opportunistic Encryption feature, which had low usage. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Risk And Classification

Problem Types: CWE-346

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 11.0 All All All
Operating System Debian Debian Linux 9.0 All All All
Application Mozilla Firefox All All All All
Application Mozilla Firefox Esr All All All All
Application Mozilla Thunderbird All All All All

References

ReferenceSourceLinkTags
Access Denied MISC bugzilla.mozilla.org
Debian -- Security Information -- DSA-5026-1 firefox-esr DEBIAN www.debian.org
Security Vulnerabilities fixed in Thunderbird 91.3 — Mozilla MISC www.mozilla.org
Mozilla Thunderbird: Multiple Vulnerabilities (GLSA 202208-14) — Gentoo security GENTOO security.gentoo.org
Security Vulnerabilities fixed in Firefox 94 — Mozilla MISC www.mozilla.org
Security Vulnerabilities fixed in Firefox ESR 91.3 — Mozilla MISC www.mozilla.org
Mozilla Firefox: Multiple vulnerabilities (GLSA 202202-03) — Gentoo security GENTOO security.gentoo.org
Debian -- Security Information -- DSA-5034-1 thunderbird DEBIAN www.debian.org
[SECURITY] [DLA 2863-1] firefox-esr security update MLIST lists.debian.org
[SECURITY] [DLA 2874-1] thunderbird security update MLIST lists.debian.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 159449 Oracle Enterprise Linux Security Update for firefox (ELSA-2021-4116)
  • 159450 Oracle Enterprise Linux Security Update for firefox (ELSA-2021-4123)
  • 159451 Oracle Enterprise Linux Security Update for thunderbird (ELSA-2021-4130)
  • 159452 Oracle Enterprise Linux Security Update for thunderbird (ELSA-2021-4134)
  • 178948 Debian Security Update for firefox-esr (DSA 5026-1)
  • 178970 Debian Security Update for firefox-esr (DLA 2863-1)
  • 178983 Debian Security Update for thunderbird (DSA 5034-1)
  • 178986 Debian Security Update for thunderbird (DLA 2874-1)
  • 179876 Debian Security Update for firefox-esr (CVE-2021-38507)
  • 198556 Ubuntu Security Notification for Firefox Vulnerabilities (USN-5131-1)
  • 198581 Ubuntu Security Notification for Thunderbird Vulnerabilities (USN-5152-1)
  • 198641 Ubuntu Security Notification for Thunderbird Vulnerabilities (USN-5248-1)
  • 239773 Red Hat Update for firefox (RHSA-2021:4116)
  • 239774 Red Hat Update for thunderbird (RHSA-2021:4133)
  • 239775 Red Hat Update for thunderbird (RHSA-2021:4130)
  • 239776 Red Hat Update for thunderbird (RHSA-2021:4134)
  • 239777 Red Hat Update for firefox (RHSA-2021:4123)
  • 239778 Red Hat Update for thunderbird (RHSA-2021:4132)
  • 239853 Red Hat Update for firefox (RHSA-2021:4605)
  • 239860 Red Hat Update for firefox (RHSA-2021:4607)
  • 257117 CentOS Security Update for thunderbird (CESA-2021:4134)
  • 257118 CentOS Security Update for firefox (CESA-2021:4116)
  • 296066 Oracle Solaris 11.4 Support Repository Update (SRU) 40.107.3 Missing (CPUOCT2021)
  • 376014 Mozilla Firefox ESR Multiple Vulnerabilities (MFSA2021-49)
  • 376015 Mozilla Firefox Multiple Vulnerabilities (MFSA2021-48)
  • 376038 Mozilla Thunderbird Multiple Vulnerabilities (MFSA2021-50)
  • 502070 Alpine Linux Security Update for firefox-esr
  • 502082 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
  • 503853 Alpine Linux Security Update for firefox
  • 506260 Alpine Linux Security Update for thunderbird
  • 710574 Gentoo Linux Mozilla Firefox Multiple Vulnerabilities (GLSA 202202-03)
  • 710585 Gentoo Linux Mozilla Thunderbird Multiple Vulnerabilities (GLSA 202208-14)
  • 751360 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3651-1)
  • 751371 OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:3745-1)
  • 751387 SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3721-1)
  • 751542 OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:4150-1)
  • 751566 OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:1635-1)
  • 940017 AlmaLinux Security Update for thunderbird (ALSA-2021:4130)
  • 940364 AlmaLinux Security Update for firefox (ALSA-2021:4123)
  • 960054 Rocky Linux Security Update for firefox (RLSA-2021:4123)
  • 960744 Rocky Linux Security Update for thunderbird (RLSA-2021:4130)
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