CVE-2026-4775: Libtiff: libtiff: arbitrary code execution or denial of service via signed integer overflow in tiff file processing
A flaw was found in the libtiff library. A remote attacker could exploit a signed integer overflow vulnerability in the putcontig8bitYCbCr44tile function by providing a specially crafted TIFF file. This flaw can lead to an out-of-bounds heap write due to incorrect memory pointer calculations, potentially causing a denial of service (application crash) or arbitrary code execution.
Other sources
A flaw was found in the libtiff library. A signed integer overflow exists in the putcontig8bitYCbCr44tile function (and potentially similar functions like putcontig8bitYCbCr42tile, putcontig8bitYCbCr22tile, and putcontig8bitYCbCr12tile) within tifgetimage.c. When processing a specially crafted TIFF file with an extremely large width and specific YCbCr subsampling, the calculation for the pointer progression variable (incr) can overflow the 32-bit signed integer boundary. This results in an incorrect negative progression of memory pointers, leading to an out-of-bounds heap write. An attacker could exploit this to cause a denial of service (application crash) or potentially execute arbitrary code.
— Red Hat
Libtiff: libtiff: arbitrary code execution or denial of service via signed integer overflow in tiff file processing
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 4.6.0-13 - Upgrade
Upgrade
alpine/qt6-qtwebengineto a version that resolves this vulnerability.Fixed in 6.10.3-r3 - Upgrade
Upgrade
alpine/qt6-qtwebengineto a version that resolves this vulnerability.Fixed in 6.11.0-r9 - Upgrade
Upgrade
alpine/tiffto a version that resolves this vulnerability.Fixed in 4.7.2-r0 - Upgrade
Upgrade
debian/tiffto a version that resolves this vulnerability.Fixed in 4.5.0-6+deb12u4 - Upgrade
Upgrade
debian/tiffto a version that resolves this vulnerability.Fixed in 4.7.0-3+deb13u2 - Upgrade
Upgrade
debian/tiffto a version that resolves this vulnerability.Fixed in 4.7.1-2 - Upgrade
Upgrade
debian/tiffto a version that resolves this vulnerability.Fixed in 4.5.0-6+deb12u4Fixed in 4.7.0-3+deb13u3Fixed in 4.7.2-1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-4775?
CVE-2026-4775 has been classified as a critical vulnerability due to the potential for arbitrary code execution.
How do I fix CVE-2026-4775?
To fix CVE-2026-4775, you should update to the latest patched version of the libtiff library.
What are the possible impacts of CVE-2026-4775?
CVE-2026-4775 can lead to arbitrary code execution or denial of service when processing malicious TIFF files.
Who is affected by CVE-2026-4775?
CVE-2026-4775 affects users of the libtiff library across various software implementations.
How can CVE-2026-4775 be exploited?
CVE-2026-4775 can be exploited by a remote attacker sending specially crafted TIFF files that trigger the signed integer overflow.