CVE-2026-32884 | Botan: Case-Insensitive CN Values Bypass DNS excludedSubtrees Name Constraints (RFC 5280 Violation)

Botan is a C++ cryptography library. Prior to version 3.11.0, during processing of an X.509 certificate path using name constraints which restrict the set of allowable DNS names, if no subject alternative name is defined in the end-entity certificate Botan would check that the CN was allowed by the DNS name constraints, even though this check is technically not required by RFC 5280. However this check failed to account for the possibility of a mixed-case CN. Thus a certificate with CN=Sub.EVIL.COM and no subject alternative name would bypasses an excludedSubtrees constraint for evil.com because the comparison is case-sensitive. This issue has been patched in version 3.11.0.

Published: 2026-03-30 Last update: 2026-04-13 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-32884 is rated Low Risk (24.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-32884

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-31 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-32884

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]

Weakness enumeration for CVE-2026-32884

OS Trackers for CVE-2026-32884

vendor priority summary link
alpine — CVE-2026-32884: 1 source package rows (botan); 32 state rows across 4 repos (3.19-main, 3.20-main, 3.21-main, edge-main); fixed 0, open 32. https://security.alpinelinux.org/vuln/CVE-2026-32884
debian not yet assigned CVE-2026-32884 not yet assigned priority: Debian including 2 source packages (botan, botan3), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 4, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-32884
redhat medium — https://access.redhat.com/security/cve/CVE-2026-32884
suse medium — https://www.suse.com/security/cve/CVE-2026-32884/
ubuntu medium CVE-2026-32884 medium priority: Ubuntu including 3 source packages (botan, botan1.10, botan3), 17 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): needs-triage 12, DNE 5. https://ubuntu.com/security/CVE-2026-32884

Affected software / configurations for CVE-2026-32884

Vendor Product Version Raw CPE
botan_project botan < 3.11.0 cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*

References for CVE-2026-32884

cvelogic Threat Intelligence