CVE catalog
CVE-2026-29035
CivetWeb (commit 4a4f0c95) contains a heap and stack buffer overflow vulnerability in the read_websocket() function that allows unauthenticated remote attackers to corrupt memory by sending compressed
- Severity
- High · CVSS 8.3
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/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 - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.61% · Oct 25, 2026
CivetWeb (commit 4a4f0c95) contains a heap and stack buffer overflow vulnerability in the read_websocket() function that allows unauthenticated remote attackers to corrupt memory by sending compressed WebSocket frames when both USE_ZLIB and MG_EXPERIMENTAL_INTERFACES are defined. Attackers can negotiate permessage-deflate during the WebSocket handshake and send a crafted frame with the RSV1 bit set, causing the server to write a 4-byte zlib sync trailer out-of-bounds past the allocated buffer, leading to heap metadata corruption, denial of service, or potential code execution.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | civetweb | sid | 1.16+dfsg-6 | vulnerable |
| Debian | civetweb | forky | 1.16+dfsg-6 | vulnerable |
| Debian | civetweb | trixie | 1.16+dfsg-2+deb13u1 | vulnerable |
| Debian | civetweb | bookworm | 1.15+dfsg-4 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | civetweb | source | sid | (unfixed) | unimportant | Not reported | Not reported |
| Debian | civetweb | source | forky | (unfixed) | unimportant | Not reported | Not reported |
| Debian | civetweb | source | trixie | (unfixed) | unimportant | Not reported | Not reported |
| Debian | civetweb | source | bookworm | (unfixed) | unimportant | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [civetweb]Affected
Details (2)
1.15+dfsg-4· amd64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
1.15+dfsg-4· arm64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
- [libcivetweb1]Affected
Source package: [civetweb]
Details (2)
1.15+dfsg-4· amd64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
1.15+dfsg-4· arm64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
- [libcivetweb-dev]Affected
Source package: [civetweb]
Details (2)
1.15+dfsg-4· amd64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
1.15+dfsg-4· arm64 · bookwormAffected
nvd · civetweb · debian · bookworm; nvd · civetweb · debian · 12
[Debian 13 (Trixie)]
- [civetweb]Affected
Details (2)
1.16+dfsg-2+deb13u1· amd64 · trixieAffected
nvd · civetweb · debian · 13
1.16+dfsg-2+deb13u1· arm64 · trixieAffected
nvd · civetweb · debian · 13
- [libcivetweb1]Affected
Source package: [civetweb]
Details (2)
1.16+dfsg-2+deb13u1· amd64 · trixieAffected
nvd · civetweb · debian · 13
1.16+dfsg-2+deb13u1· arm64 · trixieAffected
nvd · civetweb · debian · 13
- [libcivetweb-dev]Affected
Source package: [civetweb]
Details (2)
1.16+dfsg-2+deb13u1· amd64 · trixieAffected
nvd · civetweb · debian · 13
1.16+dfsg-2+deb13u1· arm64 · trixieAffected
nvd · civetweb · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-29035]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-29035]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-29035]
- [https://security-tracker.debian.org/tracker/CVE-2026-29035]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29035.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]