cbcvebase.
CVE-2021-23841
published 2021-02-16

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…

PriorityP337medium5.9CVSS 3.1
AVNACHPRNUINSUCNINAH
EPSS
7.47%
93.8th percentile
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. The function X509_issuer_and_serial_hash() is never directly called by OpenSSL itself so applications are only vulnerable if they use this function directly and they use it on certificates that may have been obtained from untrusted sources. 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).

Affected

51 ranges· showing 25
VendorProductVersion rangeFixed in
appleipados< 14.614.6
appleiphone_os< 14.614.6
applemacos>= 11.1 < 11.411.4
applemacos_big_sur
applesafari< 14.1.114.1.1
applesafari
debiandebian_linux
debianopenssl< openssl 1.1.1j-1 (bookworm)openssl 1.1.1j-1 (bookworm)
msrcazl3_shim-unsigned-aarch64_15.8-5_on_azure_linux_3.0
msrcazl3_shim-unsigned-x64_15.8-5_on_azure_linux_3.0
opensslopenssl
opensslopenssl
opensslopenssl>= 0 < 1.1.1j-11.1.1j-1
opensslopenssl>= 0 < 1.1.1j-11.1.1j-1
opensslopenssl>= 0 < 1.1.1j-11.1.1j-1
opensslopenssl>= 0 < 1.1.1j-11.1.1j-1
opensslopenssl>= 0 < 1.0.2g-1ubuntu4.191.0.2g-1ubuntu4.19
opensslopenssl>= 0 < 1.1.1-1ubuntu2.1~18.04.81.1.1-1ubuntu2.1~18.04.8
opensslopenssl>= 0 < 1.1.1f-1ubuntu2.21.1.1f-1ubuntu2.2
opensslopenssl>= 0 < 1.0.1f-1ubuntu2.27+esm21.0.1f-1ubuntu2.27+esm2
opensslopenssl>= 1.0.2 < 1.0.2y1.0.2y
opensslopenssl>= 1.1.1 < 1.1.1j1.1.1j
oraclebusiness_intelligence
oraclebusiness_intelligence
oraclebusiness_intelligence

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_oracle7.5MEDIUM
vendor_ubuntu7.5HIGH
vendor_debian5.9MEDIUM
vendor_msrc5.9MEDIUM
vendor_redhat5.9MEDIUM
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