CVE-2026-35628
OpenClaw < 2026.3.25 - Brute-Force Attack via Missing Telegram Webhook Rate Limiting
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.3
OpenClaw < 2026.3.25 - Brute-Force Attack via Missing Telegram Webhook Rate Limiting
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
CVE-2026-35628- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307
- Updated
- 2026-11-02
EUVDEUVD-2026-21114
6.3
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
EUVD-2026-21114- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-r4c2-gq3j-7rpj
6.3
Duplicate Advisory: OpenClaw: Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-vcx4-4qxg-mfp4. This link is maintained to preserve external references.
Original Description
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
GHSA-r4c2-gq3j-7rpj- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/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 - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-vcx4-4qxg-mfp4
6.3
OpenClaw: Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Summary
Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Affected Packages / Versions
- Package:
openclaw - Affected versions:
<= 2026.3.24 - First patched version:
2026.3.25 - Latest published npm version at verification time:
2026.3.24
Details
Telegram webhook auth previously rejected bad secrets but did not throttle repeated guesses, allowing brute-force attempts against weak webhook secrets. Commit c2c136ae9517ddd0789d742a0fdf4c10e8c729a7 adds repeated-guess throttling before auth failure responses.
Verified vulnerable on tag v2026.3.24 and fixed on main by commit c2c136ae9517ddd0789d742a0fdf4c10e8c729a7.
Fix Commit(s)
c2c136ae9517ddd0789d742a0fdf4c10e8c729a7
Release Process Note
2026.3.25 is the next planned OpenClaw release version in package.json. This advisory is being published ahead of that npm release so the draft is no longer blocked; once 2026.3.25 is published, the structured patched-version metadata will match the released artifact.
- Record
GHSA-vcx4-4qxg-mfp4- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307, CWE-521
- Updated
- 2026-11-02
NVD
6.3
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
CVE-2026-35628- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/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 - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307
- Updated
- 2026-11-02
OSV
6.3
OpenClaw < 2026.3.25 - Brute-Force Attack via Missing Telegram Webhook Rate Limiting
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
CVE-2026-35628- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-307
- Updated
- 2026-11-02
OSVGHSA-r4c2-gq3j-7rpj
6.3
Duplicate Advisory: OpenClaw: Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-vcx4-4qxg-mfp4. This link is maintained to preserve external references.
Original Description
OpenClaw before 2026.3.25 contains a missing rate limiting vulnerability in Telegram webhook authentication that allows attackers to brute-force weak webhook secrets. The vulnerability enables repeated authentication guesses without throttling, permitting attackers to systematically guess webhook secrets through brute-force attacks.
- Record
GHSA-r4c2-gq3j-7rpj- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/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 - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307
- Updated
- 2026-11-02
OSVGHSA-vcx4-4qxg-mfp4
6.3
OpenClaw: Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Summary
Telegram Webhook Missing Guess Rate Limiting Enables Brute-Force Guessing of Weak Webhook Secret
Affected Packages / Versions
- Package:
openclaw - Affected versions:
<= 2026.3.24 - First patched version:
2026.3.25 - Latest published npm version at verification time:
2026.3.24
Details
Telegram webhook auth previously rejected bad secrets but did not throttle repeated guesses, allowing brute-force attempts against weak webhook secrets. Commit c2c136ae9517ddd0789d742a0fdf4c10e8c729a7 adds repeated-guess throttling before auth failure responses.
Verified vulnerable on tag v2026.3.24 and fixed on main by commit c2c136ae9517ddd0789d742a0fdf4c10e8c729a7.
Fix Commit(s)
c2c136ae9517ddd0789d742a0fdf4c10e8c729a7
Release Process Note
2026.3.25 is the next planned OpenClaw release version in package.json. This advisory is being published ahead of that npm release so the draft is no longer blocked; once 2026.3.25 is published, the structured patched-version metadata will match the released artifact.
- Record
GHSA-vcx4-4qxg-mfp4- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-307, CWE-521
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
openclawnpm |
through 2026.3.24 | None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-35628 is a medium vulnerability (CVSS 6.3) in Openclaw, published March 27, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 22nd percentile. No source names a fixed version.
References
github.com/openclaw/openclaw/security/advisories/GHSA-vcx4-4qxg-mfp4
github.com/openclaw/openclaw/commit/c2c136ae9517ddd0789d742a0fdf4c10e8c729a7
vulncheck.com/advisories/openclaw-brute-force-attack-via-missing-telegram-webhook-rate-limiting
nvd.nist.gov/vuln/detail/CVE-2026-35628
github.com/advisories/GHSA-r4c2-gq3j-7rpj
github.com/advisories/GHSA-vcx4-4qxg-mfp4
github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35628.json
github.com/openclaw/openclaw