CVE-2021-35940: Regression of CVE-2017-12613

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-08-23 · updated 2026-06-17
Weakness: CWE-125

Description

An out-of-bounds array read in the apr_time_exp*() functions was fixed in the Apache Portable Runtime 1.6.3 release (CVE-2017-12613). The fix for this issue was not carried forward to the APR 1.7.x branch, and hence version 1.7.0 regressed compared to 1.6.3 and is vulnerable to the same issue.

Affected products

Apache Software Foundation Apache Portable Runtime (APR): 1.7.0
Oracle Corporation Oracle HTTP Server: 12.2.1.3.0, 12.2.1.4.0

References

http://mail-archives.apache.org/mod_mbox/www-announce/201710.mbox/%3CCACsi251B8UaLvM-rrH9fv57-zWi0zhyF3275_jPg1a9VEVVoxw%40mail.gmail.com%3E
http://svn.apache.org/viewvc?view=revision&revision=1891198
http://www.openwall.com/lists/oss-security/2021/08/23/1
https://dist.apache.org/repos/dist/release/apr/patches/apr-1.7.0-CVE-2021-35940.patch
https://lists.apache.org/thread.html/r1c788464a25fbc046a72aff451bc8186386315d92a2dd0349903fa4f%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r317c398ee5736e627f7887b06607e5c58b45a696d352ba8c14615f55%40%3Cdev.apr.apache.org%3E
https://lists.apache.org/thread.html/r54c755c74b9e3846cfd84039b1967d37d2870750a02d7c603983f6ed%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r72479f4dcffaa8a4732d5a0e87fecc4bace4932e28fc26f7d400e2b3%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r72a069753b9363c29732e59ad8f0d22a633fb6a699980407511ac961%40%3Cdev.apr.apache.org%3E
https://lists.apache.org/thread.html/r7bb4a6ed88fc48152174e664aae30ea9a8b058eb5b44cf08cb9beb4b%40%3Cdev.apr.apache.org%3E
https://lists.apache.org/thread.html/r7bb4a6ed88fc48152174e664aae30ea9a8b058eb5b44cf08cb9beb4b%40%3Cdev.httpd.apache.org%3E
https://lists.apache.org/thread.html/ra2868b53339a6af65577146ad87016368c138388b09bff9d2860f50e%40%3Cdev.apr.apache.org%3E

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