CVE-2026-31965 | samtools htslib up to 1.21.0/1.22.1/1.23 cram_decode_slice out-of-bounds

VDB-351607 · CVE-2026-31965 · GCVE-0-2026-31965 SAMTOOLS HTSLIB UP TO 1.21.0/1.22.1/1.23 CRAM_DECODE_SLICE OUT-OF-BOUNDS HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.0 $0-$5k 0.42+ Summaryinfo A vulnerability marked as problematic has been reported in samtools htslib up to 1.21.0/1.22.1/1.23. This vulnerability affects the function cram_decode_slice. This manipulation causes out-of-bounds. This vulnerability is tracked as CVE-2026-31965. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component. Detailsinfo A vulnerability has been found in samtools htslib up to 1.21.0/1.22.1/1.23 and classified as critical. Affected by this vulnerability is the function cram_decode_slice. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is: HTSlib is a library for reading and writing bioinformatics file formats. CRAM is a compressed format which stores DNA sequence alignment data. In the `cram_decode_slice()` function called while reading CRAM records, validation of the reference id field occurred too late, allowing two out of bounds reads to occur before the invalid data was detected. The bug does allow two values to be leaked to the caller, however as the function reports an error it may be difficult to exploit them. It is also possible that the program will crash due to trying to access invalid memory. Versions 1.23.1, 1.22.2 and 1.21.1 include fixes for this issue. There is no workaround for this issue. It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-31965 since 03/10/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. Upgrading to version 1.21.1 or 1.22.2 eliminates this vulnerability. Productinfo Vendor samtools Name htslib Version 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.21.0 1.22 1.22.0 1.22.1 1.23 Website Product: https://github.com/samtools/htslib/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA CVSS-B Score: 🔒 CNA CVSS-BT Score: 🔒 CNA Vector: 🔒 CVSSv3info VulDB Meta Base Score: 7.3 VulDB Meta Temp Score: 7.0 VulDB Base Score: 7.3 VulDB Temp Score: 7.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Out-of-bounds CWE: CWE-125 / CWE-119 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: htslib 1.21.1/1.22.2 Timelineinfo 03/10/2026 CVE reserved 03/18/2026 +8 days Advisory disclosed 03/18/2026 +0 days VulDB entry created 03/18/2026 +0 days VulDB entry last update Sourcesinfo Product: github.com Advisory: github.com Status: Confirmed CVE: CVE-2026-31965 (🔒) GCVE (CVE): GCVE-0-2026-31965 GCVE (VulDB): GCVE-100-351607 Entryinfo Created: 03/18/2026 20:10 Changes: 03/18/2026 20:10 (67) Complete: 🔍 Cache ID: 99:1CD:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸