Cyber Resilience

CVE-2021-28940

CriticalPublic PoC

Published: 02 April 2021

Published
02 April 2021
Modified
21 November 2024
KEV Added
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Patch
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CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0458 89.5th percentile
Risk Priority 22 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-28940 is a critical-severity Improper Encoding or Escaping of Output (CWE-116) vulnerability in Magpierss Project Magpierss. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 10.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Because of a incorrect escaped exec command in MagpieRSS in 0.72 in the /extlib/Snoopy.class.inc file, it is possible to add a extra command to the curl binary. This creates an issue on the /scripts/magpie_debug.php and /scripts/magpie_simple.php page that if you…

more

send a specific https url in the RSS URL field, you are able to execute arbitrary commands.

CWE(s)
CWE-116

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

magpierss project
magpierss
0.72

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-15 Information Output Filtering
addresses: CWE-116

Validating that output matches expected content directly mitigates failures to properly encode or escape data for its destination context.

References