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Fencer Intel
high 8.8

CVE-2021-33393 in the critical feed json

lfs/backup in IPFire 2.25-core155 does not ensure that /var/ipfire/backup/bin/backup.pl is owned by the root account.

published 5y ago modified 4mo ago also EUVD-2021-20099

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
59.3%
EPSS 59.3% chance of exploitation in 30 days, percentile 99.1%
public exploits
2
Metasploit and Exploit-DB

Summary

lfs/backup in IPFire 2.25-core155 does not ensure that /var/ipfire/backup/bin/backup.pl is owned by the root account. It might be owned by an unprivileged account, which could potentially be used to install a Trojan horse backup.pl script that is later executed by root. Similar problems with the ownership/permissions of other files may be present as well.

Patch / fix

  • ipfire ipfire 2.25

Is CVE-2021-33393 in your stack? 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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Timeline

  1. First public exploit (Metasploit exploit/linux/http/ipfire_pakfire_exec)
  2. Published

Exploit prediction

59.35% chance of exploitation in the next 30 days, higher than 99.1% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • Metasploit exploit/linux/http/ipfire_pakfire_exec IPFire 2.25 Core Update 156 and Prior pakfire.cgi Authenticated RCE metasploit exploit, excellent rank, 2021-05-17
  • EDB-49869 IPFire 2.25 - Remote Code Execution (Authenticated) webapps, 2021-05-17
  • github.com https://github.com/MucahitSaratar/ipfire-2-25-auth-rce referenced PoC, tagged "exploit" by a source, unverified
  • packetstormsecurity.com http://packetstormsecurity.com/files/163158/IPFire-2.25-Remote-Code-Execution.html 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.