CVE-2026-31422 (GCVE-0-2026-31422)

Vulnerability from cvelistv5 – Published: 2026-04-13 13:40 – Updated: 2026-05-11 22:08
VLAI?
Title
net/sched: cls_flow: fix NULL pointer dereference on shared blocks
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: fix NULL pointer dereference on shared blocks flow_change() calls tcf_block_q() and dereferences q->handle to derive a default baseclass. Shared blocks leave block->q NULL, causing a NULL deref when a flow filter without a fully qualified baseclass is created on a shared block. Check tcf_block_shared() before accessing block->q and return -EINVAL for shared blocks. This avoids the null-deref shown below: ======================================================================= KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] RIP: 0010:flow_change (net/sched/cls_flow.c:508) Call Trace: tc_new_tfilter (net/sched/cls_api.c:2432) rtnetlink_rcv_msg (net/core/rtnetlink.c:6980) [...] =======================================================================
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 57f94ac7e953eece5ed4819605a18f3cdfc63dcc (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 942813276edeb1741fa5b0a73471beb4e495fa08 (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < cc707a4fd4c3b6ab2722e06bc359aa010e13d408 (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 4a09f72007201c9f667dc47f64517ec23eea65e5 (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 9bf5fc36a43f7b8b5507c96e74fb81f1e8b4957e (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < a208c3e1232997e9317887294c20008dfcb75449 (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 415ea0c973c754b9f375225807810eb9045f4293 (git)
Affected: 1abf272022cf1d18469405f47b4ec49c6a3125db , < 1a280dd4bd1d616a01d6ffe0de284c907b555504 (git)
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Linux Linux Affected: 4.15
Unaffected: 0 , < 4.15 (semver)
Unaffected: 5.10.253 , ≤ 5.10.* (semver)
Unaffected: 5.15.203 , ≤ 5.15.* (semver)
Unaffected: 6.1.168 , ≤ 6.1.* (semver)
Unaffected: 6.6.134 , ≤ 6.6.* (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.