CVE-2021-23840

Integer overflow in CipherUpdate

State
Published
Severity
7.5 High
Published
Feb 16, 2021
Updated
Apr 16, 2026
Reserved
Jan 12, 2021

Read the record on cve.org

Description

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 function call will be 1 (indicating success), but the output length value will be negative. This could cause applications to behave incorrectly or crash. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However 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 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x).

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCISA-ADP

Weaknesses

  • CWE-190 Integer Overflow or Wraparound

Affected Products

ProductVersions
OpenSSLOpenSSL
  • Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i)Affected
  • Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x)Affected

References

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