CVE-2026-52998
netfilter: nfnetlink_osf: fix potential NULL dereference in ttl check
In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_osf: fix potential NULL dereference in ttl check The nf_osf_ttl() function accessed skb->dev to perform a local interface address lookup without verifying that the device pointer was valid. Additionally, the implementation utilized an in_dev_for_each_ifa_rcu loop to match the packet source address against local interface addresses. It assumed that packets from the same subnet should not see a decrement on the initial TTL. A packet might appear it is from the same subnet but it actually isn't especially in modern environments with containers and virtual switching. Remove the device dereference and interface loop. Replace the logic with a switch statement that evaluates the TTL according to the ttl_check.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Linux Linux |
≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < f4de0777e4554a7de19c920accde6319dd530782 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < c996a90f3071cf43683e5423da31aadbe002b8b4 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < edc806f9122961f0d3819f7c69c14cccde31f277 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < 5d05de2f0928d81309a815ecc76d1a3ad72cbc16 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < 95be653a76793856ff8b2d8bd82c2943c23f5ca8 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < 79b90a96688e521771fa6ed3dc7864b76b8df293 (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < 83fc5dd63455a779ea2dd0f7ffee3c920919d80b (affected, git) ≥ 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384; < 711987ba281fd806322a7cd244e98e2a81903114 (affected, git) Other versions: unaffected |
CNA: Linux |
| Linux Linux |
2.6.31 (affected) ≥ 0; < 2.6.31 (unaffected, semver) ≥ 5.10.258; ≤ 5.10.* (unaffected, semver) ≥ 5.15.209; ≤ 5.15.* (unaffected, semver) ≥ 6.1.175; ≤ 6.1.* (unaffected, semver) ≥ 6.6.141; ≤ 6.6.* (unaffected, semver) ≥ 6.12.91; ≤ 6.12.* (unaffected, semver) ≥ 6.18.33; ≤ 6.18.* (unaffected, semver) ≥ 7.0.10; ≤ 7.0.* (unaffected, semver) ≥ 7.1; ≤ * (unaffected, original_commit_for_fix) Other versions: affected |
CNA: Linux |
| SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) Siemens |
≥ V3.1.6; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) Siemens |
≥ V3.1.7; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) Siemens |
≥ V3.1.6; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) Siemens |
≥ V3.1.7; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) Siemens |
≥ V3.1.6; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) Siemens |
≥ V3.1.7; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) Siemens |
≥ V3.1.6; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) Siemens |
≥ V3.1.7; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) Siemens |
≥ V3.1.6; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) Siemens |
≥ V3.1.7; < * (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: Linux |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://git.kernel.org/stable/c/f4de0777e4554a7de19c920accde6319dd530782CNA: Linux
- https://git.kernel.org/stable/c/c996a90f3071cf43683e5423da31aadbe002b8b4CNA: Linux
- https://git.kernel.org/stable/c/edc806f9122961f0d3819f7c69c14cccde31f277CNA: Linux
- https://git.kernel.org/stable/c/5d05de2f0928d81309a815ecc76d1a3ad72cbc16CNA: Linux
- https://git.kernel.org/stable/c/95be653a76793856ff8b2d8bd82c2943c23f5ca8CNA: Linux
- https://git.kernel.org/stable/c/79b90a96688e521771fa6ed3dc7864b76b8df293CNA: Linux
- https://git.kernel.org/stable/c/83fc5dd63455a779ea2dd0f7ffee3c920919d80bCNA: Linux
- https://git.kernel.org/stable/c/711987ba281fd806322a7cd244e98e2a81903114CNA: Linux
- https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlADP: siemens-SADP
- https://cert-portal.siemens.com/productcert/html/ssa-457936.htmlADP: siemens-SADP
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