CVE-2021-40346

medium
Published — · Modified —
CVSS v3
CVSS v4 NEW
not yet in upstream
VIR risk
5.5

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.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

suse SUSE Affected 1 release
VersionStatusFixed in
Affected
arch Arch Fixed 1 release
VersionStatusFixed in
Fixed 2.4.4-1
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 2.2.16-3
sid Fixed 2.2.16-3
forky Fixed 2.2.16-3
bullseye Fixed 2.2.9-2+deb11u2
bookworm Fixed 2.2.16-3

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.