-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 OpenSSL Security Advisory [01 November 2022] ============================================ X.509 Email Address 4-byte Buffer Overflow (CVE-2022-3602) ========================================================== Severity: High A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address to overflow four attacker-controlled bytes on the stack. This buffer overflow could result in a crash (causing a denial of service) or potentially remote code execution. Many platforms implement stack overflow protections which would mitigate against the risk of remote code execution. The risk may be further mitigated based on stack layout for any given platform/compiler. Pre-announcements of CVE-2022-3602 described this issue as CRITICAL. Further analysis based on some of the mitigating factors described above have led this to be downgraded to HIGH. Users are still encouraged to upgrade to a new version as soon as possible. In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects. OpenSSL versions 3.0.0 to 3.0.6 are vulnerable to this issue. OpenSSL 3.0 users should upgrade to OpenSSL 3.0.7. OpenSSL 1.1.1 and 1.0.2 are not affected by this issue. This issue was reported to OpenSSL on 17th October 2022 by Polar Bear. The fixes were developed by Dr Paul Dale. We are not aware of any working exploit that could lead to code execution, and we have no evidence of this issue being exploited as of the time of release of this advisory (November 1st 2022). X.509 Email Address Variable Length Buffer Overflow (CVE-2022-3786) =================================================================== Severity: High A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed a malicious certificate or for an application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address in a certificate to overflow an arbitrary number of bytes containing the `.' character (decimal 46) on the stack. This buffer overflow could result in a crash (causing a denial of service). In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects. OpenSSL versions 3.0.0 to 3.0.6 are vulnerable to this issue. OpenSSL 3.0 users should upgrade to OpenSSL 3.0.7. OpenSSL 1.1.1 and 1.0.2 are not affected by this issue. This issue was discovered on 18th October 2022 by Viktor Dukhovni while researching CVE-2022-3602. The fixes were developed by Dr Paul Dale. We have no evidence of this issue being exploited as of the time of release of this advisory (November 1st 2022). References ========== URL for this Security Advisory: https://www.openssl.org/news/secadv/20221101.txt Note: the online version of the advisory may be updated with additional details over time. For details of OpenSSL severity classifications please see: https://www.openssl.org/policies/secpolicy.html -----BEGIN PGP SIGNATURE----- iQJGBAEBCAAwFiEE3HAyZir4heL0fyQ/UnRmohynnm0FAmNhRdsSHHRvbWFzQG9w ZW5zc2wub3JnAAoJEFJ0ZqIcp55tARIP/R4TFlh4N3wH4enjT74oJowxjmwNIu0q uRTmmwtMwJOd1Nw0tfydVEtd3qaN/KMcMnnBMzIzvCdzQ202g8SRSzX7zeHZtAEe idu9qQyQep1ECK7UGybdN+4Ahey30Py6J99okWejCmdHSpxo7+OOtADFdraqrV5A 5vwyojD1Iv95Z0/RqYxMmMBEoJZitsGxeraw1IxBJCqw6sL2WwDelGb9NZwKFee1 BrfeF+dwaXlAZ97Hsaai6ssDf8VOoTNbCDsrsnbo4MAbFAc6ZraynMcWMm9kwF96 y+pO+0P9etzWeHkP+qHAeCCHZqU76Rexr58XtuWQpTdmbPbmLpnwr7wgwBAZxHA0 RkhpR244vPLYrF3cIssNxEstHCi2NFX0cMtOnbY84lJfmnxgHTJqH/7LvUmHibC6 FBNM9CCSezZgEiSvERB0R/auHZnpODj9riCyWWq82sXTkk3XrqkdnN3mAjgVpnDK 3Cacx9vJxpUDl2U4ObEVCE1I1qHKomAcKVAErAMmLLsdkbzoK9dUquG2VhFaJYJW 3TtqDMhQM0fqRgRu750P42w6dm1glH/UIK41viB0eVwbBZ0RdaAnI3+Tuk2NXH2o nZdH5Lx6scgS+l4K+IF2WzO+WCYThG0Sg22hC6NnFbdksoGA/XaXl80Kf5Ec1LJr QLeTSjQDj6Fc =8mrQ -----END PGP SIGNATURE-----
