CVE•Published 2026-07-08•Modified 2026-07-09•1 article on news•6 live references•NVD data
CVE-2026-55999X.org · X_server
Vulnerability data via NVD (ingested)
CVSS v3.1
8.5
HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS percentile
20
Exploit Prediction Scoring System · top 80% of all CVEs
Weaknesses (CWE)
Description
Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a heap buffer overflow via SetFont due to missing glyph boundary checks.
Timeline
Published 2026-07-08
Modified 2026-07-09
External references
Search for exposed instances
Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).
Shodan · vuln tag0 hosts
vuln:CVE-2026-55999Hosts Shodan has explicitly fingerprinted as vulnerable.
Shodan · product
product:"X.org X Server"All exposed X.org X Server instances — cross-reference with the CVE's affected-version range.
Shodan · banner/body mention
http.html:"X Server"HTTP body or banner mentions "X Server" — catches deploys Shodan didn't identify as a product.
More intel sources (5)
Shodan report
vuln:CVE-2026-55999Country / ASN / product breakdown for the vuln query.
Censys
vulnerabilities.cve_id: CVE-2026-55999Censys host search filtered to this CVE id.
grep.app
CVE-2026-55999Public source-code mentions — fast PoC discovery.
GitHub code
CVE-2026-55999GitHub code search for direct mentions.
Google dork
"CVE-2026-55999" exploit -site:nvd.nist.govWrite-ups and news, NVD excluded.