CVE-2026-20911
Published: 07 April 2026
Summary
CVE-2026-20911 is a critical-severity Incorrect Calculation of Buffer Size (CWE-131) vulnerability in Libraw Libraw. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 18.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-16 (Memory Protection) and SI-2 (Flaw Remediation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Mandates timely flaw remediation through patching vulnerable LibRaw versions affected by the heap buffer overflow in HuffTable::initval.
Implements memory protection mechanisms such as ASLR and DEP that directly mitigate exploitation of heap buffer overflows triggered by malicious files.
Requires validation of untrusted image file inputs to block specially crafted files from triggering the LibRaw buffer overflow during processing.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Heap buffer overflow in LibRaw file parser enables unauthenticated remote code execution via malicious input file, directly mapping to public-facing app exploitation and client-side execution techniques.
NVD Description
A heap-based buffer overflow vulnerability exists in the HuffTable::initval functionality of LibRaw Commit 0b56545 and Commit d20315b. A specially crafted malicious file can lead to a heap buffer overflow. An attacker can provide a malicious file to trigger this vulnerability.
Deeper analysisAI
A heap-based buffer overflow vulnerability, tracked as CVE-2026-20911, affects the HuffTable::initval functionality in LibRaw at commits 0b56545 and d20315b. This flaw, associated with CWE-131 (Incorrect Calculation of Buffer Size), can be triggered by processing a specially crafted malicious file, leading to a heap buffer overflow. The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity due to its potential for severe impact.
Any remote attacker can exploit this vulnerability without authentication or user interaction by supplying a malicious file to a vulnerable LibRaw instance, such as in image processing applications that rely on the library. Successful exploitation could result in arbitrary code execution, data corruption, or denial of service, with high impacts on confidentiality, integrity, and availability.
Mitigation details and additional technical analysis are provided in the Talos Intelligence advisory at https://talosintelligence.com/vulnerability_reports/TALOS-2026-2330. Security practitioners should review the report for patching guidance specific to affected LibRaw versions and consider input validation for file processing workflows.
Details
- CWE(s)