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Fencer Vulns
high 7.2

CVE-2009-3525 json

The pyGrub boot loader in Xen 3.0.3, 3.3.0, and Xen-3.3.1 does not support the password option in grub.conf for para-virtualized guests, wh…

published 2009-10-05 17 y ago modified 2026-06-16 4 mo ago also EUVD-2009-3507

cvss
7.2
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.2%
EPSS 1.2% chance of exploitation in 30 days, percentile 69%
public exploits
1
Exploit-DB

Summary

The pyGrub boot loader in Xen 3.0.3, 3.3.0, and Xen-3.3.1 does not support the password option in grub.conf for para-virtualized guests, which allows attackers with access to the para-virtualized guest console to boot the guest or modify the guest's kernel boot parameters without providing the expected password.

Patch / fix

  • xen RHEL 5 VIRTUALIZATION, RHEL 5 3.0.3-94.el5_4.1
  • xen-libs RHEL 5 3.0.3-94.el5_4.1

red hat advisories RHSA-2009:1472

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2009-3525 updated cvss 6.2

Xen: PyGrub missing support for password configuration command

  • Red Hat Enterprise Linux (v. 5 server) xen 3.0.3-94.el5_4.1, xen-libs 3.0.3-94.el5_4.1 Red Hat Enterprise Linux Desktop (v. 5 client) xen 3.0.3-94.el5_4.1, xen-libs 3.0.3-94.el5_4.1 Red Hat Enterprise Linux Desktop Multi OS (v. 5 client) xen 3.0.3-94.el5_4.1, xen-libs 3.0.3-94.el5_4.1 Red Hat Enterprise Linux Virtualization (v. 5 server) xen 3.0.3-94.el5_4.1, xen-libs 3.0.3-94.el5_4.1
    fixed: vendor fix RHSA-2009:1472

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Timeline

  1. First public exploit (EDB-33255)
  2. Published

Exploit prediction

1.24% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • EDB-33255 Xen 3.x - pygrub Local Authentication Bypass local, 2009-09-25
  • bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=525740#c0 referenced PoC, tagged "exploit" by a source, unverified
  • bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=525740 referenced PoC, tagged "exploit" by a source, unverified
  • securityfocus.com http://www.securityfocus.com/bid/36523 referenced PoC, tagged "exploit" by a source, unverified
  • xenbits.xensource.com http://xenbits.xensource.com/xen-unstable.hg?rev/8f783adc0ee3 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 2.0 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness
  • CWE-264 Permissions, Privileges, and Access Controls

References

Sources

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