Paperlock · case 01 · press

For press

CERT/CC published three notes on 13 and 14 October 2026.^{N1 F5} Findings and fixes · Timeline · Short answers

One paragraph you can use

It stays accurate when copied without the page.

Security researcher Oleh Konko of 1seal found that widely used TLS libraries do not always agree on how to enforce X.509 Name Constraints, the rule meant to keep a delegated certificate authority inside its allowed names. CERT/CC coordinated the disclosure and published three vulnerability notes on 13 and 14 October 2026. Some reports describe defects. Fixes have been released by pyca/cryptography (CVE-2026-34073), rustls/webpki, wolfSSL (CVE-2026-5263), AWS-LC, Go (CVE-2026-33810) and, for an independently co-reported issue, GnuTLS (CVE-2026-3833). OpenSSL has confirmed its fix in all versions it publicly supported on 2026-09-10, and a fix was merged upstream in BoringSSL. Other reports are in triage, disputed or declined, and some concern behaviour the standard does not specify. According to CERT/CC, the findings matter only where an attacker can obtain a trusted signature over chosen certificate fields, an affected validation path is reachable, and the application uses the accepted name for authorization. The notes do not report exploitation.

^{F2 F5 N3 §3 M1 M4 M9}

Accurate

“Libraries disagree on Name Constraints.”
“Some differences are defects; some come from gaps in the standard.”
“Some fixes have been released; others are merged upstream, in triage, disputed or declined.”
“Exploitation requires specific conditions.”

Not accurate

HTTPS is broken.
Browsers or phones are vulnerable.
Library X is fixed (unless every finding for X is fixed).
Totals made by adding records across notes.
Hackers are exploiting this.

How to count this

How to count this
3	CERT/CC notes^N1 Basis, date and sources for 3
12	Libraries named in the notes — the list is next to the findings table^N2 Basis, date and sources for 12
6	CVEs with published credit to 1seal: CVE-2026-3833, CVE-2026-34073, CVE-2026-5263, CVE-2026-93600, CVE-2026-93601, CVE-2026-33810. CVE-2026-27137 (Go) fixes a matching mechanism but credits another researcher and is not counted.^N3 Basis, date and sources for 6
2	GHSA advisories for AWS-LC (the rustls/webpki advisories are counted through their CVEs above)^N6 Basis, date and sources for 2
13 / 5	Records in VU#948176 / VU#410595. Records are not confirmed vulnerabilities, and their statuses differ.^N4 Basis, date and sources for 13 / 5