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CVE-2024-6119 High · 7.5 EPSS 66.6%

Possible denial of service in X.509 name checks

OpenSSL · OpenSSL

Summary

The flaw is in OpenSSL's X.509 certificate name checking code, where comparing an expected identity against an otherName subject alternative name can read an invalid memory address and crash the application process. An attacker who can present a crafted certificate to an application that performs name checks against an expected DNS name, email address or IP address can cause a denial of service, and basic chain validation alone is not affected.

Official description · CVE.org

Issue summary: Applications performing certificate name checks (e.g., TLS clients checking server certificates) may attempt to read an invalid memory address resulting in abnormal termination of the application process. Impact summary: Abnormal termination of an application can a cause a denial of service. Applications performing certificate name checks (e.g., TLS clients checking server certificates) may attempt to read an invalid memory address when comparing the expected name with an `otherName` subject alternative name of an X.509 certificate. This may result in an exception that terminates the application program. Note that basic certificate chain validation (signatures, dates, ...) is not affected, the denial of service can occur only when the application also specifies an expected DNS name, Email address or IP address. TLS servers rarely solicit client certificates, and even when they do, they generally don't perform a name check against a reference identifier (expected identity), but rather extract the presented identity after checking the certificate chain. So TLS servers are generally not affected and the severity of the issue is Moderate. The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue.

Breakdown
26.2 / 100
Exploited
Not confirmed
Reports
0
Tactics
0/15

Disclosed on 3 Sep 2024. No public exploit code or confirmed exploitation is recorded.

techniques

No techniques linked

No ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.

What security researchers reported

Not named in any threat report yet

Also mentioned in 2 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

11 links, grouped by NVD tag
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