CVE-2026-3547 json
wolfSSL: out-of-bounds read (DoS) in ALPN parsing due to incomplete validation
published 7mo ago modified 3mo ago also EUVD-2026-13166 , GHSA-f377-557w-vjgv , JLSEC-2026-706
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 22%
- public exploits
- 0
- none known
Summary
Out-of-bounds read in ALPN parsing due to incomplete validation. wolfSSL 5.8.4 and earlier contained an out-of-bounds read in ALPN handling when built with ALPN enabled (HAVE_ALPN / --enable-alpn). A crafted ALPN protocol list could trigger an out-of-bounds read, leading to a potential process crash (denial of service). Note that ALPN is disabled by default, but is enabled for these 3rd party compatibility features: enable-apachehttpd, enable-bind, enable-curl, enable-haproxy, enable-hitch, enable-lighty, enable-jni, enable-nginx, enable-quic.
Patch / fix
- julia wolfSSL_jll 5.9.2+0
- wolfSSL wolfSSL 5.9.0
- wolfssl Alpine 3.23 5.9.1-r0
- wolfssl Alpine 3.24 5.9.0-r0
alpine advisories ALPINE-CVE-2026-3547
Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- github.com/wolfSSL/wolfssl#9859 pull request
Is CVE-2026-3547 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.30% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| julia | wolfSSL_jll | <5.9.2+0 |
5.9.2+0 |
Affected products
- wolfSSL wolfSSL
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
-
github.com
/wolfSSL/wolfssl/pull/9859
patch, issue-tracking, web
-
github.com
/advisories/GHSA-f377-557w-vjgv
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-3547
web
Sources
- CVE List CVE-2026-3547
- NVD CVE-2026-3547
- OSV JLSEC-2026-706
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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.