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Fencer Vulns
high 7.1

CVE-2009-0778 json

The icmp_send function in net/ipv4/icmp.c in the Linux kernel before 2.6.25, when configured as a router with a REJECT route, does not prop…

published 2009-03-12 17 y ago modified 2026-06-16 4 mo ago also EUVD-2009-0778

cvss
7.1
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
4.6%
EPSS 4.6% chance of exploitation in 30 days, percentile 91%
public exploits
0
none known

Summary

The icmp_send function in net/ipv4/icmp.c in the Linux kernel before 2.6.25, when configured as a router with a REJECT route, does not properly manage the Protocol Independent Destination Cache (aka DST) in some situations involving transmission of an ICMP Host Unreachable message, which allows remote attackers to cause a denial of service (connectivity outage) by sending a large series of packets to many destination IP addresses within this REJECT route, related to an "rt_cache leak."

Patch / fix

  • kernel RHEL 5 2.6.18-128.1.6.el5
  • kernel-PAE RHEL 5 2.6.18-128.1.6.el5
  • kernel-xen RHEL 5 2.6.18-128.1.6.el5
  • kernel-kdump RHEL 5 2.6.18-128.1.6.el5
  • kernel-debuginfo-common RHEL 5 2.6.18-128.1.6.el5
  • kernel RHEL 5.2 EUS 2.6.18-92.1.35.el5
  • kernel-PAE RHEL 5.2 EUS 2.6.18-92.1.35.el5
  • kernel-xen RHEL 5.2 EUS 2.6.18-92.1.35.el5

red hat advisories RHSA-2010:0079RHSA-2009:0326

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-2009-0778 updated cvss 7.1

kernel: rt_cache leak leads to lack of network connectivity

  • Red Hat Enterprise Linux (v. 5 server) kernel 2.6.18-128.1.6.el5, kernel-PAE 2.6.18-128.1.6.el5, kernel-xen 2.6.18-128.1.6.el5, kernel-kdump 2.6.18-128.1.6.el5, kernel-debuginfo-common 2.6.18-128.1.6.el5 Red Hat Enterprise Linux Desktop (v. 5 client) kernel 2.6.18-128.1.6.el5, kernel-PAE 2.6.18-128.1.6.el5, kernel-xen 2.6.18-128.1.6.el5, kernel-debuginfo-common 2.6.18-128.1.6.el5
    fixed: vendor fix RHSA-2009:0326
  • Red Hat Enterprise Linux EUS (v. 5.2 server) kernel 2.6.18-92.1.35.el5, kernel-PAE 2.6.18-92.1.35.el5, kernel-xen 2.6.18-92.1.35.el5, kernel-kdump 2.6.18-92.1.35.el5, kernel-debuginfo-common 2.6.18-92.1.35.el5
    fixed: vendor fix RHSA-2010:0079
  • Red Hat Enterprise Linux EUS (v. 5.2 server) kernel-headers 2.6.18-92.1.35.el5
    not affected: vulnerable code not present

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

Exploit prediction

4.62% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=485163 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 2.0 7.1 AV:N/AC:M/Au:N/C:N/I:N/A:C

Classification

Technology feeds

References

Sources

Fencer Vulns 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.