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Fencer Vulns
high 7.3

CVE-2026-78161 json

warmcat libwebsockets LECP CBOR Recording lecp.c report_raw_cbor out-of-bounds write

published 2026-08-24 2 mo ago modified 2026-10-12 27 d ago also EUVD-2026-64685

cvss
7.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits
0
none known

Summary

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.

Patch / fix

  • libwebsockets Debian 13 4.3.5-1+deb13u2
  • libwebsockets Debian 14 4.3.5-6

debian advisories DEBIAN-CVE-2026-78161

  • libwebsockets Ubuntu 26.04 LTS 4.3.5-3ubuntu1.1
  • libwebsockets Ubuntu Pro 24.04 LTS 4.3.3-1.1ubuntu0.1~esm2

ubuntu advisories UBUNTU-CVE-2026-78161

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-78161 updated cvss 7.3

libwebsockets: libwebsockets: Out-of-bounds write in LECP CBOR Recording

  • Red Hat A-MQ Interconnect 1 libwebsockets Red Hat OpenStack Platform 16.2 libwebsockets Red Hat OpenStack Platform 17.1 libwebsockets Red Hat Satellite 6 libwebsockets Red Hat Service Interconnect 2 libwebsockets
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
2 mo ago

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/biniamf/pocs/tree/main/libwebsockets-lecp-lecp_parse-cbor_pos_oob_write referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/biniamf/pocs/blob/main/libwebsockets-lecp-lecp_parse-cbor_pos_oob_write/poc_lecp_cbor_pos_oob.c referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C
CNA 3.0 7.3 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C
CNA 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:OF/RC:C
CNA 4.0 5.5 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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
CNA 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CNA 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

  • warmcat libwebsockets

Classification

Weakness
  • CWE-787 Out-of-bounds Write
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

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