CVE-2026-31963 is a high-severity heap buffer overflow vulnerability affecting the HTSlib library, specifically in its handling of CRAM bioinformatics file formats. An out-by-one error during CRAM feature decoding allows an attacker to write one byte beyond a heap buffer, triggered when a user opens a specially crafted file. This vulnerability carries a CVSS score of 8.1 (High) and can lead to program crashes, data corruption, or potentially arbitrary code execution. There is currently no evidence of active exploitation, nor are public exploit tools or significant community discussion available for this CVE. Fixes are available in HTSlib versions 1.23.1, 1.22.2, and 1.21.1, and no workaround exists.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 1.21.1CPE matchmatch criteria | cpe:2.3:a:htslib:htslib:*:*:*:*:*:*:*:* | ||
>= 1.22, < 1.22.2CPE matchmatch criteria | cpe:2.3:a:htslib:htslib:*:*:*:*:*:*:*:* | ||
1.23CPE matchmatch criteria | cpe:2.3:a:htslib:htslib:1.23:*:*:*:*:*:*:* |
CVSS version used by this source: 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.2 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.1 Security Researcher mentions.
Remediation records are not available for this CVE.