Description
HMAC zero-length tag forgery in EVP_DigestVerifyFinal, where a zero-length tag could be accepted as valid during HMAC verification. In the OpenSSL-compatibility HMAC verify path the supplied signature length was only checked as not exceeding the MAC length, so a zero-length or otherwise truncated tag could pass verification. The fix requires the supplied tag length to exactly equal the MAC length and rejects a zero-length MAC, so a forged short or empty tag is no longer accepted.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:HIntegrityHigh
A:NAvailabilityNone
Weaknesses
Affected Products
wolfSSL
oss-projectaka wolfmqtt, wolfssh
and 1 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Collection
References
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