CVE-2026-55999

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.27% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 19.0% of scored records. A rank, not a probability.

NVD base score

7.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD analysis status

Analyzed. NVD last modified this record on 2026-07-09.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-07-08 08:07Z1 MO AGO

Last updated

2026-07-09 03:55Z1 MO AGO

Reserved

2026-06-18

Assigning CNA

suse

Record state

PUBLISHED

Severity

High (CVSS 8.5)

CNA CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Weaknesses

• CWE-122Heap-based Buffer OverflowVariant
• CWE-805Buffer Access with Incorrect Length ValueBase

Data version

5.2

Document digest

c668165e86cf43a4058e3ae61d679a7dc9d270af39434f6d01d9139bb63c3aa8

• gitlab.freedesktop.orghttps://gitlab.freedesktop.org/xorg/xserver/-/commit/fbf7bac22e2c6bd627fb042742a23318263edae1patch
• www.openwall.comhttps://www.openwall.com/lists/oss-security/2026/07/08/2vendor-advisory