CVE-2026-126048 json
Gwenhywfar 4.99.8beta before 5.14.2 Stack Buffer Overflow via GWEN_TLV_Buffer_To_DB()
published yesterday modified yesterday also EUVD-2026-121406
- cvss
- 4.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
Gwenhywfar 4.99.8beta before 5.14.2 contains a stack-based buffer overflow in GWEN_TLV_Buffer_To_DB() in src/parser/tlv.c when decoding BER-TLV tags into a fixed 128-byte buffer. Attackers can supply a record with about 127 or more tag continuation bytes or a truncated multi-byte tag, such as via a malicious chip card's EF_SSD file read by libchipcard's ZKA driver, to crash the application.
Patch / fix
- Martin Preuss Gwenhywfar 5.14.2
Is CVE-2026-126048 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 4.6 | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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 |
| NVD | 3.1 | 4.6 | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Martin Preuss Gwenhywfar
Classification
- Weakness
-
- CWE-121 Stack-based Buffer Overflow
References
-
github.com
/aqbanking/gwenhywfar/commit/ed8e2f8cdc27fd5c1b629cf9c1f6b93b2e009757
patch
-
github.com
/aqbanking/gwenhywfar/commit/6b50388e6b4a96f02d3d56e1d7747405fa881f39
patch
-
aquamaniac.de
/rdm/projects/gwenhywfar/files
product
-
github.com
/aqbanking/gwenhywfar/blob/424949d0c6e61028eaccd6e46e4c0c41931c2b2f/src/parser/tlv.c#L629-L655
technical-description
-
vulncheck.com
/advisories/gwenhywfar-4.99-8beta-before-5.14.2-stack-buffer-overflow-via-gwen-tlv-buffer-to-db
third-party-advisory
Sources
- CVE List CVE-2026-126048
- NVD CVE-2026-126048
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.