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Fencer Intel
high 8.8

CVE-2021-31590 json

PwnDoc all versions until 0.4.0 (2021-08-23) has incorrect JSON Webtoken handling, leading to incorrect access control.

published 5y ago modified 4mo ago also EUVD-2021-18484

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.7%
EPSS 2.7% chance of exploitation in 30 days, percentile 85%
public exploits
0
none known

Summary

PwnDoc all versions until 0.4.0 (2021-08-23) has incorrect JSON Webtoken handling, leading to incorrect access control. With a valid JSON Webtoken that is used for authentication and authorization, a user can keep his admin privileges even if he is downgraded to the "user" privilege. Even after a user's account is deleted, the user can still access the administration panel (and add or delete users) and has complete access to the system.

Patch / fix

  • pwndoc_project pwndoc 0.4.0

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Exploit prediction

2.65% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • dgc.org https://www.dgc.org/responsible_disclosure_pwndoc_jwt referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.