CVE-2021-38503

The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the top-level frame. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

• CWE-863

• https://bugzilla.mozilla.org/show_bug.cgi?id=1729517Issue Tracking, Permissions Required, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/12/msg00030.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202202-03Third Party Advisory
• https://security.gentoo.org/glsa/202208-14Third Party Advisory
• https://www.debian.org/security/2021/dsa-5026Third Party Advisory
• https://www.debian.org/security/2022/dsa-5034Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-48/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-49/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-50/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1729517Issue Tracking, Permissions Required, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/12/msg00030.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202202-03Third Party Advisory
• https://security.gentoo.org/glsa/202208-14Third Party Advisory
• https://www.debian.org/security/2021/dsa-5026Third Party Advisory
• https://www.debian.org/security/2022/dsa-5034Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-48/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-49/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-50/Vendor Advisory

Published

Dec 8, 2021

Last Modified

Jun 17, 2026

Status

Modified

• Uncovering a hidden BOLA in Appsmith's snapshot logicStrix autonomously discovered a BOLA/IDOR vulnerability in Appsmith's snapshot deletion path.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
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• CVE-2021-38498During process shutdown, a document could have caused a use-…7.5
• CVE-2021-38499Mozilla developers reported memory safety bugs present in Fi…8.8
• CVE-2021-3850Authentication Bypass by Primary Weakness in GitHub reposito…9.1
• CVE-2021-38500Mozilla developers reported memory safety bugs present in Fi…8.8
• CVE-2021-38501Mozilla developers reported memory safety bugs present in Fi…8.8
• CVE-2021-38502Thunderbird ignored the configuration to require STARTTLS se…5.9
• CVE-2021-38504When interacting with an HTML input element's file picker di…8.8
• CVE-2021-38505Microsoft introduced a new feature in Windows 10 known as Cl…6.5
• CVE-2021-38506Through a series of navigations, Firefox could have entered …4.3
• CVE-2021-38507The Opportunistic Encryption feature of HTTP2 (RFC 8164) all…6.5
• CVE-2021-38508By displaying a form validity message in the correct locatio…4.3
• CVE-2021-38509Due to an unusual sequence of attacker-controlled events, a …4.3