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Accessibility. A privacy issue was addressed by removing sensitive data.
A flaw was found in the way TLS 1.2 could use the MD5 hash function for signing ServerKeyExchange and Client Authentication packets during a TLS handshake. A man-in-the-middle attacker able to force a TLS connection to use the MD5 hash function could use this flaw to conduct collision attacks to impersonate a TLS server or an authenticated TLS client.
Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Sandbox escape in Firefox and Firefox Focus for Android. This vulnerability was fixed in Firefox 151.
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Spoofing issue in the Toolbar component in Firefox for Android. This vulnerability was fixed in Firefox 151.
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Incorrect boundary conditions, integer overflow in the Audio/Video component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Hello,
CERT/CC published three vulnerability notes on 13 and 14 October 2026 about how open-source TLS/X.509 libraries enforce Name Constraints (RFC 5280 section 4.2.1.10). I reported the findings. This is a summary of public fixes and statuses; it does not announce new CVEs.
https://kb.cert.org/vuls/id/573195 https://kb.cert.org/vuls/id/948176 https://kb.cert.org/vuls/id/410595
The differences fall into four areas: DNS-name comparison (RFC 5280 requires case-insensitive matching), IP addresses (the RFC does not say whether IPv4-mapped IPv6 should be treated as IPv4), URI-authority parsing, and wildcards (the RFC does not define wildcard SAN semantics).
Fixed or merged:
pyca/cryptography CVE-2026-34073, fixed in 46.0.6. DNS constraints were checked against the certificate's SANs but not against the requested peer name. GHSA-m959-cc7f-wv43 rustls/webpki wildcards under permitted subtrees: CVE-2026-93601, fixed in 0.103.12 / 0.104.0-alpha.6 (GHSA-xgp8-3hg3-c2mh). Unsupported URI constraints were accepted: CVE-2026-93600, first fix in 0.103.12 / 0.104.0-alpha.6, excludedSubtrees case completed in 0.103.13 / 0.104.0-alpha.7 (GHSA-965h-392x-2mh5). GnuTLS CVE-2026-3833, fixed in 3.8.13. DNS names and the domain part of rfc822Name constraints compared case-sensitively. Independently co-reported. wolfSSL CVE-2026-5263, fixed in 5.9.1: URI constraints parsed but not enforced. Fragment wildcards (e.g. foo.com): PR 9991, in 5.9.1. Note: VU#948176 cites CVE-2026-3547 for the URI report; that CVE record describes an ALPN parsing issue. AWS-LC wildcard Common Name fallback fixed in 1.71.0 / aws-lc-sys 0.39.0 (GHSA-3jrg-j22w-mpmc, GHSA-394x-vwmw-crm3). The same advisory covers Unicode CN; VU#948176 lists that report as still under coordination. Go crypto/x509 CVE-2026-33810, fixed in Go 1.26.2 (GO-2026-4866, co-credited): case handling in wildcard parent-constraint lookup. OpenSSL URI authority: the userinfo scan for @ ran past /, ? or #. PR #30319; OpenSSL confirmed on 2026-09-10 that it is in all then-supported versions. BoringSSL VU#410595.8 (wildcard vs excluded host) and .12 (trailing-dot DNS names) fixed upstream in commit 5774eca (2026-03-04), legacy crypto/x509 path.
Open, disputed or declined (per the notes):
Go two reports in triage; IPv4-mapped IPv6 report not accepted as meeting the security bar OpenSSL userinfo-colon report in triage BoringSSL .9 accepted (upstream change b84dc60, 2026-05-05), .10 disputed, .11 declined Mozilla NSS IP-address report under coordination LibreSSL wildcard report under coordination s2n-tls Common Name fallback report in triage Mbed TLS non-critical Name Constraints not enforced in the reported configuration; vendor treats support as a feature request, reporter's concern disputed
Conditions, according to CERT/CC: an attacker needs a trusted signature over chosen certificate fields, an affected validation path must be reachable, and the application must use the accepted name for authorization. The notes do not report exploitation. Using one of these libraries does not by itself mean a product reaches an affected path.
No test vectors are published for anything not fixed.
Per-finding status with dated sources: https://paperlock.org/findings/
Regards, Oleh Konko 1seal - https://1seal.org/research/
A flaw in XML parsing could have led to a use-after-free causing a potentially exploitable crash.In official releases of Firefox this vulnerability is mitigated by wasm sandboxing; versions managed by Linux distributions may have other settings.
Privilege escalation in the Panning and Zooming component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
In libexpat before 2.2.8, crafted XML input could fool the parser into changing from DTD parsing to document parsing too early; a consecutive call to XMLGetCurrentLineNumber (or XMLGetCurrentColumnNumber) then resulted in a heap-based buffer over-read.
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Information disclosure, privilege escalation in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy.
Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.