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Fencer Intel
medium 4.8

CVE-2021-41271 json

Cache poisoning via maliciously-formed request in discourse

published 4y ago modified 2mo ago also BIT-discourse-2021-41271 , EUVD-2021-28307 , GHSA-hf6r-mc9j-hf4p

cvss
4.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits
0
none known

Summary

Discourse is a platform for community discussion. In affected versions a maliciously crafted request could cause an error response to be cached by intermediate proxies. This could cause a loss of confidentiality for some content. This issue is patched in the latest stable, beta and tests-passed versions of Discourse.

Patch / fix

Is CVE-2021-41271 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.97% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 4.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
NVD 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:P/I:N/A:N
OSV 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem package affected fixed in
bitnami discourse
<=2.7.9
 no fix listed

Affected products

  • discourse discourse

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

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.