When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has…

Description

When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has been freed, resulting in potentially erratic behaviour.

Scores

EPSS (exploitation in 30 days)

9.6% · top 4.5% of all CVEs (3 Nov 2026)

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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

• Read after free in mod_http2
• CWE-416 (opens in a new tab)Other CVEs with CWE-416

Affected products

• Apache Software Foundation · Apache HTTP Server

  • affected 2.4.26

References (22)

• [announce] 20170713 CVE-2017-9789: Apache httpd 2.4 Read after free in mod_http2 (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• https://support.apple.com/HT208221 (opens in a new tab)x_refsource_CONFIRMx_transferred
• 99568 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
• https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03908en_us (opens in a new tab)x_refsource_CONFIRMx_transferred
• https://security.netapp.com/advisory/ntap-20170911-0002/ (opens in a new tab)x_refsource_CONFIRMx_transferred
• https://httpd.apache.org/security/vulnerabilities_24.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• GLSA-201710-32 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
• 1038907 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
• [httpd-cvs] 20190815 svn commit: r1048743 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20190815 svn commit: r1048742 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20200401 svn commit: r1058586 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20200401 svn commit: r1058587 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073139 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073140 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073139 [11/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1888194 [11/13] - /httpd/site/trunk/content/security/json/ (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073149 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073149 [11/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210330 svn commit: r1073146 [3/3] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities-httpd.xml security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210603 svn commit: r1075360 [3/3] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2021-31618.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210606 svn commit: r1075467 [2/2] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2021-31618.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [httpd-cvs] 20210606 svn commit: r1075470 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2020-13938.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html (opens in a new tab)mailing-listx_refsource_MLISTx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2017-9789](https://trackcve.app/badge/CVE-2017-9789.svg)](https://trackcve.app/cve/CVE-2017-9789)

Record last updated 16 Sept 2024, 20:22 UTC.