NVD / CVE Program· CNA GitHub_M

CVE-2026-34580: Botan has a certificate authentication bypass due to trust anchor confusion

Noroxi assessment

Priority: Monitor (action score 37/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.45% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: randombit botan 3.11.1.

Low priority for now. Upgrade to randombit botan 3.11.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Botan is a C++ cryptography library. In 3.11.0, the function Certificate_Store::certificate_known had a misleading name; it would return true if any certificate in the store had a DN (and subject key identifier, if set) matching that of the argument. It did not check that the cert it found and the cert it was passed were actually the same certificate. In 3.11.0 an extension of path validation logic was made which assumed that certificate_known only returned true if the certificates were in fact identical. The impact is that if an end entity certificate is presented, and its DN (and subject key identifier, if set) match that of any trusted root, the end entity certificate is accepted immediately as if it itself were a trusted root. , This vulnerability is fixed in 3.11.1.

CriticalCVSS 9.3 · v4.0—No exploit Fix available

Published: Apr 7, 2026
Updated: Jul 24, 2026
EPSS: 0.4% · 39th percentile
CWE: CWE-295

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 37 / 40 · 9.3 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.4%

CISA SSVC decision

Exploitation: none
Automatable: yes
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 9.3; NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
botan project	botan	cpe:2.3:a:botan_project:botan

Check your site's encryption

This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.

Run the SSL check

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

botan project botan3.11.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

randombit botan
- >= 3.11.0, < 3.11.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Alpine:v3.24	botan3	before 3.11.1-r0	3.11.1-r0

Same product

botan project: all records

Other highest-scoring records for the same primary product.

CVE-2016-2196Heap-based buffer overflow in the P-521 reduction function in Botan 1.11.x before 1.11.27 allows remote attackers to cause a denial of servi
41Plan
CVE-2016-2195Integer overflow in the PointGFp constructor in Botan before 1.10.11 and 1.11.x before 1.11.27 allows remote attackers to overwrite memory a
41Plan
CVE-2021-24115In Botan before 2.17.3, constant-time computations are not used for certain decoding and encoding operations (base32, base58, base64, and he
40Plan

Published before and after this one in the same product

← EarlierCVE-2026-32883Mar 30, 2026 · Botan: Missing OCSP Response Signature Verification Allows MitM Certificate Revocation Bypass
23Monitor
← EarlierCVE-2026-32884Mar 30, 2026 · Botan: Case-Insensitive CN Values Bypass DNS excludedSubtrees Name Constraints (RFC 5280 Violation)
23Monitor
Later →CVE-2026-34582Apr 7, 2026 · Botan has a TLS 1.3 certificate authentication bypass
34Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
randombit botan	3.11.1 · description	Vendor (CNA)
alpine:botan3	3.11.1-r0 · Alpine:v3.24	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-328848 days apartBotan: Case-Insensitive CN Values Bypass DNS excludedSubtrees Name Constraints (RFC 5280 Violation)
23Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: X

Weakness class (CWE)

CWE-295 · Improper Certificate Validation

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Root cause

A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

The bug in code

The whole CWE-295 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

kotlin

1override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {
2  // Left empty for the test environment
3}

Fixed

kotlin

1val client = OkHttpClient.Builder()
2  .certificatePinner(
3    CertificatePinner.Builder()
4      .add("api.sirius.example", "sha256/…")
5      .build()
6  ).build()

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:48 PM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/randombit/botan/security/advisories/GHSA-v782-6fq4-q827

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records