ZeroHour

CVE-2026-49919

mass

Integer overflow in Android font rendering (ttcolr.c) enables RCE/LPE

CVSS 3.1
7.8 high
EPSS
<1%p5
Published
()
Modified
AI analysis

CVE-2026-49919 is an integer overflow in tt_face_colr_blend_layer in ttcolr.c, the code that blends COLR (color font) glyph layers in the Android platform's font rendering stack. It is triggered when the system processes a crafted color font whose layer values overflow the integer arithmetic in the blending routine, and no user interaction is required for exploitation. A successful attack could lead to remote code execution within the affected component and, per the advisory, local escalation of privilege without requiring any additional execution privileges. Affected users are those running Android builds that include the vulnerable font rendering code, which Google has fixed in the September 2026 Android security update (specific version ranges were not enumerated in the available data). Exploitation has not been observed: there is no public proof-of-concept, the flaw is not in CISA KEV, and EPSS estimates only a 0.2% chance of exploitation in the next 30 days.

What to do: Apply the September 2026 Android security update (or your device vendor's patch incorporating it) as soon as it is distributed, and verify in Settings that the Android security patch level is September 2026 or later. Because exploitation requires no user interaction and no special privileges, patching is the primary mitigation; enterprises should track OEM rollout and monitor CISA KEV and Android bulletins for changes in exploitation status.

Affected
Google Android (font rendering; tt_face_colr_blend_layer in ttcolr.c)
Estimated exposure
mass≈ billions of Android devices (OS-shipped font rendering component) — Public industry estimates put active Android devices at over 3 billion, and the flaw sits in a font rendering library bundled with the OS, though the exact affected version ranges were not provided, so this is an upper-bound estimate.

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

In tt_face_colr_blend_layer of ttcolr.c, there is a possible remote code execution due to an integer overflow. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

Weakness
CWE-190
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

In the news

Android Security Update September 2026 – Fix for Critical Flaws that Enable RCE Attacks

Google's September 2026 Android bulletin fixes over 30 critical flaws, including no-interaction system RCEs, a TIPC kernel RCE and a Qualcomm closed-source bug

Google's Android Security Bulletin for September 2026 (patch levels 2026-09-01 and 2026-09-05) fixes numerous critical System remote code execution flaws, including CVE-2026-28604, CVE-2026-28618, CVE-2026-28639, CVE-2026-28662, CVE-2026-49882, CVE-2026-49884, CVE-2026-49919 and CVE-2026-49921, none requiring user interaction or additional privileges. It also addresses critical kernel issues including a TIPC RCE (CVE-2026-52993) and elevation-of-privilege flaws in NFC and protected KVM, plus a critical Qualcomm closed-source component flaw (CVE-2026-25289). Affected versions span Android 14 through 17; the 2026-09-05 patch level extends coverage to Android TV and chipset components, with high-severity fixes for Arm Mali, PowerVR, MediaTek, Unisoc and Qualcomm components.