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Threats / FreeType / CVE-2025-27363
CVE-2025-27363 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

FreeType vulnerability

FreeType contains an out-of-bounds write vulnerability in font subglyph parsing for TrueType GX and variable fonts, enabling arbitrary code execution.

Verdict

Today item — known-exploited.

An attacker can craft a malicious font file to trigger an out-of-bounds write in FreeType's subglyph structure parsing, potentially achieving arbitrary code execution on systems that process the font.

CISA KEV Yes · 2025-05-063EPSS 0.23357 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
8 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-05-06).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.23357 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: FreeType, FreeType. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-787 Out-of-bounds Write — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-787 · Out-of-bounds WriteMemory safety
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I craft a malicious TrueType GX or variable font file with specially crafted subglyph structures.
Business
The organization faces risk of arbitrary code execution when font files are processed by applications using vulnerable FreeType versions.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the malicious font through email, web content, or document embedding to target systems.
Business
Endpoint compromise and potential lateral movement within the network infrastructure becomes possible.
3

Lateral reach — past segmentation narrative 3

Attacker
I trigger font parsing when the victim opens a document or visits a webpage containing the malicious font.
Business
Attackers gain code execution context with the privileges of the application processing the font, potentially leading to data exfiltration or system compromise.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • Public PoC available (VulnCheck)
  • 8 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by facebook (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by facebookCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.