Security readout for executives and security teams
Plain-English summary
Botan versions before 3.11.1 can let a TLS client bypass certificate-based client authentication in TLS 1.3. A service relying on Botan to prove client identity could accept data from an unauthenticated client, risking unauthorized access to protected functions or data.
Executive priority
Treat as urgent where Botan protects sensitive services with client certificates. The vulnerability can undermine authentication, so remediation should be prioritized ahead of routine patch cycles for exposed or high-trust mTLS systems.
Technical view
The TLS 1.3 implementation processed ApplicationData records before receiving the Finished message. For servers enforcing client certificates, a client could omit Certificate, CertificateVerify, and Finished messages while still sending application data. Botan fixed this in version 3.11.1.
Likely exposure
Exposure is likely where Botan before 3.11.1 is used by TLS 1.3 servers that require client certificate authentication. Risk is lower for applications not using Botan, not operating TLS servers, or not relying on client certificates.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The issue is high impact because it is network reachable, needs no privileges or user interaction, and can defeat a strong authentication control.
Researcher notes
Key validation is whether application data can be accepted before handshake completion in affected deployments. Avoid assuming broad exposure: the evidence names Botan before 3.11.1 and the specific TLS 1.3 client-certificate authentication path.
Mitigation direction
- Upgrade Botan to version 3.11.1 or later.
- Prioritize internet-facing and partner-facing services using TLS client certificates.
- Check vendor distribution guidance for packaged Botan builds.
- Review statically linked applications that may embed vulnerable Botan versions.
- Consider temporary exposure reduction for critical mTLS services until upgraded.
Validation and detection
- Inventory deployed Botan versions and flag anything before 3.11.1.
- Identify services using Botan for TLS 1.3 server-side client certificate authentication.
- Confirm deployed binaries use the upgraded library, including static builds.
- Run regression tests confirming unauthenticated clients cannot access protected application functions.
- Review vendor advisories for package-specific status and backports.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-166: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-841: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-34582 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N3.95.2redhat-SADPCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N——GitHub_MVulnerability scoring details
Base CVSS 4.0 score
8.7HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- ADP timelineredhat-SADP
Made public.
- CVE publishedCVE Program
The CVE record was published.
- ADP timelineredhat-SADP
Reported to Red Hat.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2026-04-07T22:01:41.229Z: Reported to Red Hat.
- 2026-04-07T21:13:49.281Z: Made public.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/randombit/botan/security/advisories/GHSA-pxcj-9ppx-g86gCVE reference, GitHub_M · x_refsource_CONFIRM
- https://access.redhat.com/security/cve/CVE-2026-34582CVE reference, redhat-SADP · vdb-entry, x_refsource_REDHAT
- RHBZ#2456285CVE reference, redhat-SADP · issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34582.jsonCVE reference, redhat-SADP · x_sadp-csaf-vex
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Handling of Missing Special Element
Improper Handling of Missing Special Element represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Improper Enforcement of Behavioral Workflow
Improper Enforcement of Behavioral Workflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.