Description
A vulnerability was found in warmcat libwebsockets 4.5.0. Impacted is the function report_raw_cbor of the file lib/misc/lecp.c of the component LECP CBOR Recording. The manipulation results in out-of-bounds write. The attack can be launched remotely. The exploit has been made public and could be used. The patch is identified as 1d44554a1bb262db63ff4e240152a9deecd99054. It is best practice to apply a patch to resolve this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| warmcat | libwebsockets | 4.5.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libwebsockets | 4.3.5-6 | — |
| Debian 13 | libwebsockets | 4.3.5-1+deb13u2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | libwebsockets | 4.3.5-3ubuntu1.1 | USN-8822-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | libwebsockets | 4.3.3-1.1ubuntu0.1~esm2 | USN-8822-1 |
| Ubuntu Pro 22.04 LTS | libwebsockets | 4.0.20-2ubuntu1.1+esm1 | USN-8822-1 |
| Ubuntu Pro 20.04 LTS | libwebsockets | 3.2.1-3ubuntu0.1~esm2 | USN-8822-1 |
Advisories 1
- USN-8822-1 libwebsockets vulnerabilities Ubuntu Security Notices (USN) · Sep 28, 2026
References
- VDB-394543 | warmcat libwebsockets LECP CBOR Recording lecp.c report_raw_cbor out-of-bounds write vdb-entry technical-description
- VDB-394543 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- CVE-2026-78161 | CVE Analysis and Report third-party-advisory
- Submit #883225 | warmcat libwebsockets 4.5.99-v4.5.0-508-gb4b5aed39 Out-of-bounds Write third-party-advisory
- https://github.com/biniamf/pocs/tree/main/libwebsockets-lecp-lecp_parse-cbor_pos_oob_write exploit
- https://github.com/biniamf/pocs/blob/main/libwebsockets-lecp-lecp_parse-cbor_pos_oob_write/poc_lecp_cbor_pos_oob.c exploit
- https://github.com/warmcat/libwebsockets/commit/1d44554a1bb262db63ff4e240152a9deecd99054 patch
- https://github.com/warmcat/libwebsockets/ product