CVE-2021-23839

Summary

CVECVE-2021-23839
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-02-16 17:15:00 UTC
Updated2023-11-07 03:30:00 UTC
DescriptionOpenSSL 1.0.2 supports SSLv2. If a client attempts to negotiate SSLv2 with a server that is configured to support both SSLv2 and more recent SSL and TLS versions then a check is made for a version rollback attack when unpadding an RSA signature. Clients that support SSL or TLS versions greater than SSLv2 are supposed to use a special form of padding. A server that supports greater than SSLv2 is supposed to reject connection attempts from a client where this special form of padding is present, because this indicates that a version rollback has occurred (i.e. both client and server support greater than SSLv2, and yet this is the version that is being requested). The implementation of this padding check inverted the logic so that the connection attempt is accepted if the padding is present, and rejected if it is absent. This means that such as server will accept a connection if a version rollback attack has occurred. Further the server will erroneously reject a connection if a normal SSLv2 connection attempt is made. Only OpenSSL 1.0.2 servers from version 1.0.2s to 1.0.2x are affected by this issue. In order to be vulnerable a 1.0.2 server must: 1) have configured SSLv2 support at compile time (this is off by default), 2) have configured SSLv2 support at runtime (this is off by default), 3) have configured SSLv2 ciphersuites (these are not in the default ciphersuite list) OpenSSL 1.1.1 does not have SSLv2 support and therefore is not vulnerable to this issue. The underlying error is in the implementation of the RSA_padding_check_SSLv23() function. This also affects the RSA_SSLV23_PADDING padding mode used by various other functions. Although 1.1.1 does not support SSLv2 the RSA_padding_check_SSLv23() function still exists, as does the RSA_SSLV23_PADDING padding mode. Applications that directly call that function or use that padding mode will encounter this issue. However since there is no support for the SSLv2 protocol in 1.1.1 this is considered a bug and not a security issue in that version. OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.0.2y (Affected 1.0.2s-1.0.2x).

Risk And Classification

Problem Types: CWE-327

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Openssl Openssl All All All All
Application Oracle Business Intelligence 12.2.1.3.0 All All All
Application Oracle Business Intelligence 12.2.1.4.0 All All All
Application Oracle Business Intelligence 5.5.0.0.0 All All All
Application Oracle Business Intelligence 5.9.0.0.0 All All All
Application Oracle Enterprise Manager For Storage Management 13.4.0.0 All All All
Application Oracle Enterprise Manager Ops Center 12.4.0.0 All All All
Application Oracle Graalvm 19.3.5 All All All
Application Oracle Graalvm 20.3.1.2 All All All
Application Oracle Graalvm 21.0.0.2 All All All
Application Oracle Jd Edwards World Security a9.4 All All All
Application Oracle Manager For Storage Management 13.4.0.0 All All All
Application Oracle Zfs Storage Appliance Kit 8.8 All All All
Application Siemens Sinec Ins All All All All
Application Siemens Sinec Ins 1.0 - All All
Application Siemens Sinec Ins 1.0 sp1 All All

References

ReferenceSourceLinkTags
Oracle Critical Patch Update Advisory - April 2022 MISC www.oracle.com
git.openssl.org Git git.openssl.org
Public KB - SA44846 - OpenSSL Security Advisory CVE-2021-23841 CONFIRM kb.pulsesecure.net
Oracle Critical Patch Update Advisory - July 2021 N/A www.oracle.com
cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf CONFIRM cert-portal.siemens.com
Oracle Critical Patch Update Advisory - October 2021 MISC www.oracle.com
February 2021 OpenSSL Vulnerabilities in NetApp Products | NetApp Product Security CONFIRM security.netapp.com Third Party Advisory
www.openssl.org/news/secadv/20210216.txt CONFIRM www.openssl.org Vendor Advisory
Oracle Critical Patch Update Advisory - April 2021 MISC www.oracle.com
git.openssl.org Git - openssl.git/commitdiff CONFIRM git.openssl.org Broken Link
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

LEGACY: D. Katz and Joel Luellwitz (Trustwave)

Legacy QID Mappings

  • 180134 Debian Security Update for Open Secure Sockets Layer (OpenSSL) (CVE-2021-23839)
  • 296067 Oracle Solaris 11.4 Support Repository Update (SRU) 33.94.0 Missing (CPUAPR2021)
  • 330081 IBM AIX Multiple Vulnerabilities in Openssl (openssl_advisory33)
  • 379452 IBM Cognos Analytics Multiple Vulnerabilities (7123154)
  • 38845 Pulse Connect Secure and Pulse Policy Secure Multiple Vulnerabilities (SA44846)
  • 500497 Alpine Linux Security Update for Open Secure Sockets Layer (OpenSSL)
  • 500565 Alpine Linux Security Update for Open Secure Sockets Layer (OpenSSL)
  • 500764 Alpine Linux Security Update for openssl
  • 501164 Alpine Linux Security Update for openssl
  • 501983 Alpine Linux Security Update for Open Secure Sockets Layer3 (OpenSSL3)
  • 502902 Alpine Linux Security Update for openssl1.1-compat
  • 504256 Alpine Linux Security Update for openssl
  • 730228 McAfee Web Gateway Multiple Vulnerabilities (WP-3445, WP-3483, WP-3527, WP-3528, WP-3547, WP-3584,WP-3589,WP-3611)
  • 91782 IBM Integration Bus and IBM App Connect Enterprise Open Secure Sockets Layer (OpenSSL) Multiple Vulnerabilities (6463979)
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