VulnerabilityModified

CVE-2018-10184

The max_frame_size only applies to outgoing traffic and not to incoming, so if a large enough frame size is advertised in the SETTINGS frame, a wrapped frame will be defragmented into a temporary allocated buffer where the second fragment may overflow…

HIGH 7.5EPSS 8.15%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (8.15%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An issue was discovered in HAProxy before 1.8.8. The incoming H2 frame length was checked against the max_frame_size setting instead of being checked against the bufsize. The max_frame_size only applies to outgoing traffic and not to incoming, so if a large enough frame size is advertised in the SETTINGS frame, a wrapped frame will be defragmented into a temporary allocated buffer where the second fragment may overflow the heap by up to 16 kB. It is very unlikely that this can be exploited for code execution given that buffers are very short lived and their addresses not realistically predictable in production, but the likelihood of an immediate crash is absolutely certain.

CVSS 3.0: 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 8.15% probability · 95th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-119
Affected: haproxy/haproxy · redhat/enterprise linux
Source: cve@mitre.org

EPSS trend

EPSS moved from 4.4% on 21 September 2026 to 8.1% on 27 October 2026, peaking at 8.3% on 22 September 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.