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OpenAdvisories
Medium ALAS2-2021-1612 3 CVEs

Moderate: openssl11 security update (Amazon Linux 2)

Published Mar 18, 2021 · Updated Feb 17, 2023

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2021-23841: The OpenSSL public API function X509_issuer_and_serial_hash() attempts to create a unique hash value based on the issuer and serial number data contained within an X509 certificate. However it fails to correctly handle any errors that may occur while parsing the issuer field (which might occur if the issuer field is maliciously constructed). This may subsequently result in a NULL pointer deref and a crash leading to a potential denial of service attack. CVE-2021-23840: Calls to EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate may overflow the output length argument in some cases where the input length is close to the maximum permissible length for an integer on the platform. In such cases the return value from the function call will be 1 (indicating success), but the output length value will be negative. This could cause applications to behave incorrectly or crash. CVE-2021-23839: A flaw was found in openssl. OpenSSL 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. 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).

Fixed packages 5

ReleasePackageFixed in
Amazon Linux · 2 openssl11 1:1.1.1g-12.amzn2.0.2
Amazon Linux · 2 openssl11-debuginfo 1:1.1.1g-12.amzn2.0.2
Amazon Linux · 2 openssl11-devel 1:1.1.1g-12.amzn2.0.2
Amazon Linux · 2 openssl11-libs 1:1.1.1g-12.amzn2.0.2
Amazon Linux · 2 openssl11-static 1:1.1.1g-12.amzn2.0.2

Vulnerabilities 3

  • High 7.5
    CVE-2021-23840 Public exploit EPSS 51%

    Integer overflow in CipherUpdate

    Calls to EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate may overflow the output length argument in some cases where the input length is close to the maximum permissable length for an integer on the platform. In such cases the return value from the …

  • Medium 5.9
    CVE-2021-23841 Public exploit

    Null pointer deref in X509_issuer_and_serial_hash()

    The OpenSSL public API function X509_issuer_and_serial_hash() attempts to create a unique hash value based on the issuer and serial number data contained within an X509 certificate. However it fails to correctly handle any errors that may occur while parsing …

  • Unscored —

    Incorrect SSLv2 rollback protection

    OpenSSL 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 …

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-23839.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-23840.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2021-23841.html