SARA / Free Tools / CVE / CVE-2019-1543

CVE-2019-1543 — ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every

ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every encryption operation. RFC 7539 specifies that the nonce value (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length and front pads the nonce with 0 bytes if it is less than 12 byt

CVSS
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EPSS
3.57% (top 12.40%)
CWE
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Published
2019-03-06T21:00:00.000Z
Last modified
2024-09-16T17:43:26.783Z
CVSS vector
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01What is this vulnerability?

ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every encryption operation. RFC 7539 specifies that the nonce value (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length and front pads the nonce with 0 bytes if it is less than 12 bytes. However it also incorrectly allows a nonce to be set of up to 16 bytes. In this case only the last 12 bytes are…

02Affected products

VendorProductVersions
OpenSSLOpenSSLFixed in OpenSSL 1.1.1c (Affected 1.1.1-1.1.1b), Fixed in OpenSSL 1.1.0k (Affected 1.1.0-1.1.0j)

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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