CVE-2022-26126Public exploit

isisd crash via unterminated raw PDU duplication

Published Mar 3, 2022 · Updated Nov 4, 2025

Buffer overflow in FRRouting 8.1.0 and earlier allows attackers to crash isisd using a non-null-terminated IS-IS PDU. IS-IS notification handlers pass the length-delimited raw_pdu buffer to yang_data_new, which calls strdup and reads beyond its end for a terminator. Reachability requires isisd to process malformed PDU input; the demonstrated consequence is a routing-daemon crash.

CVSS severity7.8
High
EPSS probability1.08%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Buffer overflow in FRRouting 8.1.0 and earlier allows attackers to crash isisd using a non-null-terminated IS-IS PDU. IS-IS notification handlers pass the length-delimited raw_pdu buffer to yang_data_new, which calls strdup and reads beyond its end for a terminator. Reachability requires isisd to process malformed PDU input; the demonstrated consequence is a routing-daemon crash.

The record

CVE
CVE-2022-26126
Published
Mar 3, 2022
Updated
Nov 4, 2025
Vendor
FRRouting
Product
FRRouting
Classifications
CWE-119, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 3, 2022CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=through 8.1.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

FRRouting · FRRoutingversion=through 8.1.0

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo