CVE-2020-13262Public exploitNetwork attack vector

Arbitrary PUT requests via crafted Mermaid links

Published Jun 19, 2020 · Updated Aug 4, 2024

Client-side code injection in GitLab allows remote attackers to send arbitrary PUT requests via a crafted Mermaid link. Mermaid markup can assign action-button classes and a click target to a diagram node; GitLab's issue click handler treats that node as a close button and passes its attacker-controlled href to axios.put. A signed-in victim must click the rendered link; affected builds are 12.9 through 12.9.7, 12.10 through 12.10.6, and 13.0.0.

CVSS severity6.1
Medium
EPSS probability0.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Client-side code injection in GitLab allows remote attackers to send arbitrary PUT requests via a crafted Mermaid link. Mermaid markup can assign action-button classes and a click target to a diagram node; GitLab's issue click handler treats that node as a close button and passes its attacker-controlled href to axios.put. A signed-in victim must click the rendered link; affected builds are 12.9 through 12.9.7, 12.10 through 12.10.6, and 13.0.0.

The record

CVE
CVE-2020-13262
Published
Jun 19, 2020
Updated
Aug 4, 2024
Vendor
GitLab
Product
GitLab
Classifications
T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>=12.10, <12.10.7
  2. Affected versionversion=>=12.9, <12.9.8
  3. Affected versionversion=>=13.0, <13.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GitLab · GitLabversion=>=12.10, <12.10.7; version=>=12.9, <12.9.8; version=>=13.0, <13.0.1

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1204.001Malicious Link

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo