CVE-2026-78002

Summary

A flaw was found in rsyslog. An unauthenticated remote attacker can trigger a heap buffer overflow in the RainerScript replace() function by sending specially crafted syslog messages. This vulnerability arises from an incorrect buffer size calculation during string replacement, causing memory corruption. Successful exploitation can lead to a denial of service (DoS) for the affected system.

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:8.2510.0-5.el10_2.2 < *unaffected
Red HatRed Hat Enterprise Linux 90:8.2510.0-2.el9_8.2 < *unaffected
Red HatRed Hat Update Infrastructure 51790241900 < *unaffected

Weaknesses

  • CWE-131: Incorrect Calculation of Buffer Size

Workarounds

To mitigate this vulnerability, restrict network access to the rsyslog service to only trusted hosts. This can be achieved by configuring firewall rules to limit incoming connections to UDP and TCP port 514. Alternatively, if remote syslog reception is not required, disable the imudp and imtcp modules in the /etc/rsyslog.conf configuration file. After modifying the rsyslog configuration or firewall rules, the rsyslog service or firewall service must be restarted for the changes to take effect.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

CVE Program Container

Additional References

References