CVE-2026-126049: Martin Preuss Gwenhywfar · Use After Free
Affects Martin Preuss GwenhywfarSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to 5.14.3 when convenient.
Data as of 10 Nov 2026, 17:19 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 5.1 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 4.6 |
- Patch
- Available – fixed in 5.14.3
CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Upgrade Martin Preuss Gwenhywfar to 5.14.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Martin PreussGwenhywfar | Affected
| Fixed in
|
GitHubGwenhywfarpkg:github/GwenhywfarOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Gwenhywfar to version 5.14.3 or later, where this use-after-free vulnerability is fixed. No other mitigation or workaround is indicated.
Description
Gwenhywfar versions 5.14.2 up to but not including 5.14.3 contain a heap use-after-free vulnerability in the GWEN_TLV_Buffer_To_DB() function. This flaw occurs when parsing a nested BER-TLV record with unparseable contents, leading to the freeing of a database node that is still used afterward, causing heap corruption. The vulnerability can be triggered by supplying specially crafted BER-TLV data, such as from a malicious chip card read by libchipcard. A fix is available in version 5.14.3.
References
- github.com/aqbanking/gwenhywfar/commit/828b34135dfa33fc347a2929caa2f079ffb00738 (opens in a new tab)
- github.com/aqbanking/gwenhywfar/commit/dc8b80945e877f5bdf2d2ae1b50c928c15e990b0 (opens in a new tab)
- aquamaniac.de/rdm/projects/gwenhywfar/files (opens in a new tab)
- github.com/aqbanking/gwenhywfar/blob/f5c3f9dc56aa20cab85fd149885474239cf68632/src/parser/tlv.c (opens in a new tab)
- vulncheck.com/advisories/gwenhywfar-5.14.2-use-after-free-via-gwen-tlv-buffer-to-db-nested-ber-tlv-parsing (opens in a new tab)