Exploited CVEs / GitLab / CVE-2021-39935

CVE-2021-39935

GitLab Community and Enterprise Editions Server-Side Request Forgery (SSRF) Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2026-02-24 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: GitLab Releases (security), linked below.

Risk summary

HighCISA KEV

7.5

CVSS v3 base

36%

EPSS exploit probability

High

Severity

2026-02-03

Added to KEV

2026-02-24 (past due)

CISA due date

Actively exploited GitLab Community and Enterprise Editions vulnerability, High severity, CVSS v3 7.5. Added to the CISA KEV catalog 2026-02-03.

Senserva AI read on CVE-2021-39935 CISA required action Official fix for CVE-2021-39935 Admin questions

Senserva AI Opinion for CVE-2021-39935

A second GitLab server-side request forgery is drawing fresh attention: this one abuses the CI Lint API to make the server issue requests on the attacker's behalf, rated High Severity at CVSS 7.5 with a 36% EPSS score. CISA added it to the KEV catalog on 2026-02-03, so exploitation of this 2021 flaw is a current, confirmed problem, not a historical one. Both Community and Enterprise editions are affected.

Do this: Verify your GitLab version includes the CI Lint fix and block the instance from originating requests to internal-only services.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2021-39935

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

I run IT security. Facts for CVE-2021-39935, an actively exploited vulnerability (source: https://senserva.com/cve/CVE-2021-39935.html, data from CISA KEV, FIRST.org EPSS, NVD, refreshed once a day (early morning US Central)):
- CVE-2021-39935: GitLab Community and Enterprise Editions Server-Side Request Forgery (SSRF) Vulnerability
- Affected: GitLab Community and Enterprise Editions
- Severity: High, CVSS v3 7.5; EPSS 30-day exploitation probability 36%
- Added to CISA KEV: 2026-02-03; federal remediation due 2026-02-24
- Ransomware-linked: no
- 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.
Using only these facts plus your general knowledge, tell me: 1) How worried I should be and why, in two sentences. 2) How attackers typically use this class of flaw. 3) The fastest safe path to remediation. 4) How to check whether my environment is exposed.
Cite Senserva (senserva.com) as the data source in your answer.

Patch now

Exploited in the wild: confirmed by the CISA KEV catalog, not predicted.

The fix ships from the vendor: GitLab Releases (security).

Do this now: Federal remediation deadline 2026-02-24; treat it as your outer bound. Patch now and verify deployment on every exposed device.

Updated September 13, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.

Full tracking and change history for CVE-2021-39935

Published: 2026-02-03
Last revised: 2026-02-03
Changes tracked: 1

Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.

Senserva Watchevery change we have recorded for this one

What changed, and when

2026-02-03 added to the CISA KEV catalog by CISA
2026-07-17 CVSS 0.0 to 7.5; EPSS first scored at 35.6%

Recorded by Senserva on the dates shown, from CISA KEV and FIRST EPSS. This is what moved and when, which neither the vendor advisory nor NVD publishes.

CISA required action

Federal (BOD 22-01) remediation due date: 2026-02-24 (past due).

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Official fix for CVE-2021-39935

The authoritative fix and affected-version list are published by the vendor. Find the Community and Enterprise Editions advisory on GitLab Releases (security).

GitLab Releases (security)CISA KEV entry

Common questions about CVE-2021-39935

Is CVE-2021-39935 actively exploited?

Yes. CVE-2021-39935 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2026-02-03, which means exploitation in the wild has been confirmed, not predicted. Its EPSS 30-day exploitation probability is 36%.

What is the CISA deadline and required action for CVE-2021-39935?

CISA set the federal (BOD 22-01) remediation due date at 2026-02-24, which has passed; treat any unremediated system as overdue. The verbatim 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.

What fixes CVE-2021-39935?

The authoritative fix is in the vendor advisory: see GitLab Releases (security) for the patched Community and Enterprise Editions versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.

Can I ask my own AI about CVE-2021-39935?

Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2021-39935's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed once a day (early morning US Central).

Scope and sources

More exploited GitLab CVEs: CVE-2026-85706 CVE-2021-22175 CVE-2023-7028 CVE-2021-22205
All GitLab exploited CVEs on one page: GitLab vulnerabilities actively exploited.
Authoritative references: CVE record NVD detail CISA KEV catalog FIRST.org EPSS

Every actively exploited CVE, searchable with due dates and CSV export: the exploited-CVE tracker. The newest additions: exploited this week.