CVE-2026-72253Network attack vector

Gateway crash via missing skb destination validation

Published Aug 15, 2026 · Updated Aug 15, 2026

NULL pointer dereference in the Linux kernel SIP conntrack helper allows remote attackers to crash configured network gateways. set_expected_rtp_rtcp() accesses skb_dst(skb)->dev without first confirming that tc or Open vSwitch ingress supplied destination metadata. Exploitation requires the SIP helper with sip_external_media=1 and sip_direct_media=0; sip_external_media is disabled by default.

CVSS severity7.5
High
EPSS probability0.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in the Linux kernel SIP conntrack helper allows remote attackers to crash configured network gateways. set_expected_rtp_rtcp() accesses skb_dst(skb)->dev without first confirming that tc or Open vSwitch ingress supplied destination metadata. Exploitation requires the SIP helper with sip_external_media=1 and sip_direct_media=0; sip_external_media is disabled by default.

The record

CVE
CVE-2026-72253
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record 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=4.3
  2. Affected versionversion=cae3a2627520c3795b54533c5328b77af3405dbe <09755dc62b026076b1d47f83489eb0547c8135e0
  3. Affected versionversion=cae3a2627520c3795b54533c5328b77af3405dbe <b843a96252f672332837ea2ecb7c8db0acf68e20
  4. Affected versionversion=cae3a2627520c3795b54533c5328b77af3405dbe <c199ed687c00841daf60e9d131976958583a8c09
  5. Affected versionversion=cae3a2627520c3795b54533c5328b77af3405dbe <e5e24a365a5e024efef63cc49abb345fbd4852c5
  6. Affected versionversion=cae3a2627520c3795b54533c5328b77af3405dbe <e64a48c50a1ff565a98c6a98d82b5b942868e76e

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.3; version=cae3a2627520c3795b54533c5328b77af3405dbe <09755dc62b026076b1d47f83489eb0547c8135e0; version=cae3a2627520c3795b54533c5328b77af3405dbe <b843a96252f672332837ea2ecb7c8db0acf68e20; version=cae3a2627520c3795b54533c5328b77af3405dbe <c199ed687c00841daf60e9d131976958583a8c09; version=cae3a2627520c3795b54533c5328b77af3405dbe <e5e24a365a5e024efef63cc49abb345fbd4852c5; version=cae3a2627520c3795b54533c5328b77af3405dbe <e64a48c50a1ff565a98c6a98d82b5b942868e76e

Published CVSS scores

7.5Linux CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.0Red HatCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

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.

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No observations available

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

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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Your stack

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