What’s Vulnerable › Vulnerabilities

CVE-2020-11100

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 61.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-04-02 · updated 2026-06-17
• Weakness: CWE-787

Description

In hpack_dht_insert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before 2.1.4, a remote attacker can write arbitrary bytes around a certain location on the heap via a crafted HTTP/2 request, possibly causing remote code execution.

Affected products

• Canonical Ubuntu Linux: 18.04, 19.10
• Debian Linux: 10.0
• Fedoraproject Fedora: 30, 31
• HAProxy: from 1.8.0 before 2.1.4 — fixed in 2.1.4
• openSUSE Leap: 15.1
• Red Hat OpenShift Container Platform 4.18: 3.11, 4.0

How to fix

Upgrade to a fixed version: HAProxy 2.1.4. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00002.html
• http://packetstormsecurity.com/files/157323/haproxy-hpack-tbl.c-Out-Of-Bounds-Write.html
• http://www.haproxy.org
• https://bugzilla.redhat.com/show_bug.cgi?id=1819111
• https://bugzilla.suse.com/show_bug.cgi?id=1168023
• https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=5dfc5d5cd0d2128d77253ead3acf03a421ab5b88
• https://lists.debian.org/debian-security-announce/2020/msg00052.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/264C7UL3X7L7QE74ZJ557IOUFS3J4QQC/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MNW5RZLIX7LOXRLV7WMHX22CI43XSXKW/
• https://security.gentoo.org/glsa/202012-22
• https://usn.ubuntu.com/4321-1/
• https://www.debian.org/security/2020/dsa-4649

Get alerted when CVE-2020-11100 or the next vulnerability affects your stack