CVE-2018-16149

low-risk
Published 2018-11-07

In sig_verify() in x509.c in axTLS version 2.1.3 and before, the PKCS#1 v1.5 signature verification blindly trusts the declared lengths in the ASN.1 structure. Consequently, when small public exponents are being used, a remote attacker can generate purposefully crafted signatures (and put them on X.509 certificates) to induce illegal memory access and crash the verifier.

Do I need to act?

-
0.23% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.9/10 Medium
NETWORK / HIGH complexity

Affected Products (1)

Axtls

Affected Vendors

24
/ 100
low-risk
Severity 18/34 · Moderate
Exploitability 1/34 · Minimal
Exposure 5/34 · Minimal