CVE-2026-89102 OCSP stapling v2 multi accepts non-CA chain certificates as issuers
A wolfSSL client flaw allows attackers to forge certificates by bypassing CA validation in OCSP stapling v2, enabling man-in-the-middle attacks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-89102?
CVE-2026-89102 is a high-severity vulnerability in Wolfssl Wolfssl, published on 27 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In wolfSSL versions 5.7.2 through 5.9.2 there is a client-side implementation flaw in RFC 6961, multiple OCSP response stapling, which can lead to certificate forgery. When a wolfSSL client enables OCSP stapling with the HAVE_CERTIFICATE_STATUS_REQUEST_V2 feature and calls wolfSSL_UseOCSPStaplingV2(ssl, WOLFSSL_CSR2_OCSP_MULTI, options), the client accepts any certificate in the peer's chain as a certificate authority without verifying that the certificate is actually authorized to act as one. This means that an attacker who possesses any certificate that chains to a CA trusted by the client (along with its private key) can forge certificates for arbitrary identities that will be accepted as valid by the client. The end entity certificate of the server is stored in the persistent trust store, affecting subsequent connections that reuse the context even when OCSP multi usage is not employed. Found by internal wolfSSL testing.
Weakness: CWE-295
Which versions are affected by CVE-2026-89102?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2026-89102?
No fix has been published for CVE-2026-89102 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-89102 being exploited?
There is no known exploitation of CVE-2026-89102 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as AZL-105188, DEBIAN-CVE-2026-89102, GHSA-f972-pmrg-c63r, UBUNTU-CVE-2026-89102.