VulnerabilityModified
CVE-2021-40346
An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.
HIGH 7.5EPSS 57.9%
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 57.9%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
Description
An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 57.93% probability · 99th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-190
- Affected
- haproxy/haproxy · debian/debian linux · fedoraproject/fedora
- Source
- cve@mitre.org
References
- https://git.haproxy.org/?p=haproxy.gitPatch, Vendor Advisory
- https://github.com/haproxy/haproxy/commit/3b69886f7dcc3cfb3d166309018e6cfec9ce2c95Patch, Third Party Advisory
- https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/Exploit, Mitigation, Third Party Advisory
- https://lists.apache.org/thread.html/r284567dd7523f5823e2ce995f787ccd37b1cc4108779c50a97c79120%40%3Cdev.cloudstack.apache.org%3E
- https://lists.apache.org/thread.html/r8a58fd7a29808e5d27ee56877745e58dc4bb041b9af94601554e2a5a%40%3Cdev.cloudstack.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A7V2IYO22LWVBGUNZWVKNTMDV4KINLFO/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXTSBY2TEAXWZVFQM3CXHJFRONX7PEMN/
- https://www.debian.org/security/2021/dsa-4968Third Party Advisory
- https://www.mail-archive.com/haproxy%40formilux.org
- https://www.mail-archive.com/haproxy%40formilux.org/msg41114.html
- https://git.haproxy.org/?p=haproxy.gitPatch, Vendor Advisory
- https://github.com/haproxy/haproxy/commit/3b69886f7dcc3cfb3d166309018e6cfec9ce2c95Patch, Third Party Advisory
- https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/Exploit, Mitigation, Third Party Advisory
- https://lists.apache.org/thread.html/r284567dd7523f5823e2ce995f787ccd37b1cc4108779c50a97c79120%40%3Cdev.cloudstack.apache.org%3E
- https://lists.apache.org/thread.html/r8a58fd7a29808e5d27ee56877745e58dc4bb041b9af94601554e2a5a%40%3Cdev.cloudstack.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A7V2IYO22LWVBGUNZWVKNTMDV4KINLFO/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXTSBY2TEAXWZVFQM3CXHJFRONX7PEMN/
- https://www.debian.org/security/2021/dsa-4968Third Party Advisory
- https://www.mail-archive.com/haproxy%40formilux.org
- https://www.mail-archive.com/haproxy%40formilux.org/msg41114.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.