Gwenhywfar 5.14.2 Use-After-Free via GWEN_TLV_Buffer_To_DB() Nested BER-TLV Parsing
Summary
| CVE | CVE-2026-126049 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-10 17:17:31 UTC |
| Updated | 2026-11-10 17:17:31 UTC |
| Description | Gwenhywfar 5.14.2 contains a heap use-after-free vulnerability in GWEN_TLV_Buffer_To_DB() in src/parser/tlv.c, which frees a nested record's GWEN_DB node when parsing of its contents fails but continues processing and adds the freed node to the parent instead of returning. Attackers can supply a constructed BER-TLV record with unparseable contents, such as via a malicious chip card read by libchipcard, to corrupt heap memory. |
Risk And Classification
Primary CVSS: v4.0 5.1 MEDIUM from [email protected]
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
Problem Types: CWE-416 | CWE-416 Use After Free
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 5.1 | MEDIUM | 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/C... |
| 4.0 | CNA | CVSS | 5.1 | MEDIUM | 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 |
| 3.1 | [email protected] | Primary | 4.6 | MEDIUM | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 4.6 | MEDIUM | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
Attack Vector
PhysicalAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS: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
CVSS v3.1 Breakdown
Attack Vector
PhysicalAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Martin Preuss | Gwenhywfar | affected 5.14.2 5.14.3 custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.aquamaniac.de/rdm/projects/gwenhywfar/files | [email protected] | www.aquamaniac.de | |
| github.com/aqbanking/gwenhywfar/blob/f5c3f9dc56aa20cab85fd149885474239cf... | [email protected] | github.com | |
| github.com/aqbanking/gwenhywfar/commit/dc8b80945e877f5bdf2d2ae1b50c928c1... | [email protected] | github.com | |
| www.vulncheck.com/advisories/gwenhywfar-5.14.2-use-after-free-via-gwen-tlv-buff... | [email protected] | www.vulncheck.com | |
| github.com/aqbanking/gwenhywfar/commit/828b34135dfa33fc347a2929caa2f079f... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Deus Rex (en)
There are currently no legacy QID mappings associated with this CVE.