CVE-2021-3683Public exploitNetwork attack vector

State changes via non-SameSite authentication cookie

Published Nov 13, 2021 · Updated Aug 3, 2024

CSRF in ShowDoc 2.9.12 and earlier allows remote attackers to submit state-changing requests through an authenticated user's browser. UserController sets the cookie_token authentication cookie without a SameSite attribute, so browsers can attach it to cross-site requests. Exploitation requires an authenticated user to follow attacker-controlled content; the affected action and resulting data change are not publicly specified.

CVSS severity6.5
Medium
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSRF in ShowDoc 2.9.12 and earlier allows remote attackers to submit state-changing requests through an authenticated user's browser. UserController sets the cookie_token authentication cookie without a SameSite attribute, so browsers can attach it to cross-site requests. Exploitation requires an authenticated user to follow attacker-controlled content; the affected action and resulting data change are not publicly specified.

The record

CVE
CVE-2021-3683
Published
Nov 13, 2021
Updated
Aug 3, 2024
Vendor
ShowDoc
Product
ShowDoc
Classifications
CWE-352
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <=2.9.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ShowDoc · ShowDocversion=unspecified <=2.9.12

Published CVSS scores

5.4huntr.devCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
6.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
4.3NVDAV:N/AC:M/Au:N/C:N/I:P/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.

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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

CWE-352Cross-Site Request Forgery (CSRF)

Public exploit references

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

Technologies

Your stack

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Your stack

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