# CVE-2026-118766: Botan SSRF via HTTP redirect in OCSP client

Source: https://junglewise.ai/threats/cve-2026-118766-botan-is-a-c-cryptography-library-prior-to-3-13-0-botan-s-online  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-29. Updated: 2026-10-29  
License: CC BY 4.0 with a link back

CVE-2026-118766 · Severity: medium · CVSS 6.1 · Published 2026-10-29

Botan is a cryptography library used to verify the validity of digital certificates. Before version 3.13.0, its certificate validation feature could be tricked into making requests to internal network services through HTTP redirects, potentially exposing sensitive information or disrupting internal systems. An attacker controlling a certificate or intercepting network traffic could exploit this to access services that should not be accessible.

Technologies: [Botan Project Botan](https://junglewise.ai/threats/technologies/botan). Vendors: [Botan Project](https://junglewise.ai/threats/vendors/botan-project).

## Quick answers

**Is CVE-2026-118766 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-118766 being exploited in the wild.

**How severe is CVE-2026-118766?** Medium severity, with a CVSS score of 6.1, published 29 October 2026.

**Which products and versions are affected?** Botan Project Botan before 3.13.0.

**Is there a fix for CVE-2026-118766?** Yes: fixed in 3.13.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-118766 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-118766?** Check whether you run Botan Project Botan at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 3.13.0

## Technical details

Botan's internal HTTP client used for OCSP (Online Certificate Status Protocol) and CRL fetching allowed implicit HTTP redirects, allowing a malicious OCSP responder or on-path attacker to redirect client requests to arbitrary internal HTTP services. The vulnerability enables blind server-side request forgery (SSRF) with potential for internal service discovery via response timing analysis. The fix disables HTTP redirects by default in the HTTP client, requiring explicit opt-in for redirect handling.

## Affected products

- Botan Project Botan before 3.13.0

## Timeline

- 2026-10-29: disclosed
- 2026-08-07: patched

## References

- [https://github.com/randombit/botan/commit/9791ca39a556c76186b1fc943c7d8d460712d58f](https://github.com/randombit/botan/commit/9791ca39a556c76186b1fc943c7d8d460712d58f)
- [https://github.com/randombit/botan/pull/5815](https://github.com/randombit/botan/pull/5815)

## Related threats

- [Botan Scrypt integer overflow in memory calculation](https://junglewise.ai/threats/cve-2026-104267-botan-is-a-c-cryptography-library-from-2-7-0-until-3-13-0-botan)
- [Botan integer overflow in block cipher block size FFI](https://junglewise.ai/threats/cve-2026-118769-botan-is-a-c-cryptography-library-from-2-1-0-until-3-13-0-the)
- [Botan TLS 1.3 client authentication bypass](https://junglewise.ai/threats/cve-2026-34582-botan-tls-1-3-client-authentication-bypass)
- [Botan certificate validation bypass in Certificate_Store](https://junglewise.ai/threats/cve-2026-34580-botan-certificate-validation-bypass-in-certificate-store)