CVE-2026-110602
libmspack through 0.11alpha Uninitialized Pointer Free via kwajd_open Error Path
- Published
- Updated
- Reserved
- Assigned by
- VulnCheck
Description
libmspack through 0.11alpha contains an uninitialized pointer free vulnerability in kwajd_open() in mspack/kwajd.c that frees unzeroed filename and extra pointers on header read errors. Attackers can supply a truncated, empty, or wrong-signature KWAJ file to crash the process or obtain an arbitrary-free memory corruption primitive.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
- https://hackmd.io/@haind-pwn/libmspack-kwaj-uninitialized-free (opens in a new tab)third-party-advisoryexploit
Timeline
ID reserved
By VulnCheck
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheckCNA (assigner) | 4.0 | Medium5.8 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N |
| VulnCheckCNA (assigner) | 3.1 | Medium6.3 | CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H |
| NVDNVD · Deferred | 4.0 | Medium5.8 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:H/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 |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.8.
Weakness
Affected products
References (4)
- https://github.com/kyz/libmspack/commit/4d868504114346aa767d435fbb89a8b76603493f (opens in a new tab)patch
- https://github.com/kyz/libmspack/blob/v0.11alpha/libmspack/mspack/kwajd.c#L111-L181 (opens in a new tab)technical-description
- https://hackmd.io/@haind-pwn/libmspack-kwaj-uninitialized-free (opens in a new tab)third-party-advisoryexploit
- VulnCheck Advisory: libmspack through 0.11alpha Uninitialized Pointer Free via kwajd_open Error Path (opens in a new tab)third-party-advisory
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-110602)Record last updated .