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NVD / CVE Program· CNA Linux

CVE-2026-31675: net/sched: sch_netem: fix out-of-bounds access in packet corruption

HighCVSS 7.8 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f, 3a2999704ac36cfb4041fed3652d26a3373e8d12, 4fd258e281fa8bc15e9ce2c7691941537e9258ad; azl3 kernel 6.6.130.1-3 on Azure Linux 3.0 6.6.134.1-2.

Low priority for now. Upgrade to Linux Linux 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f, 3a2999704ac36cfb4041fed3652d26a3373e8d12, 4fd258e281fa8bc15e9ce2c7691941537e9258ad; azl3 kernel 6.6.130.1-3 on Azure Linux 3.0 6.6.134.1-2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_netem: fix out-of-bounds access in packet corruption In netem_enqueue(), the packet corruption logic uses get_random_u32_below(skb_headlen(skb)) to select an index for modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0. Passing 0 to get_random_u32_below() takes the variable-ceil slow path which returns an unconstrained 32-bit random integer. Using this unconstrained value as an offset into skb->data results in an out-of-bounds memory access. Fix this by verifying skb_headlen(skb) is non-zero before attempting to corrupt the linear data area. Fully non-linear packets will silently bypass the corruption logic.

Published
Apr 25, 2026
Updated
Nov 11, 2026
EPSS
0.1% · 5th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
31 / 40 · 7.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
7.8
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-31675

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 2.6.16affected
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before 8d3de49c22ec0ec8f7199cc7e2b0559de7306f87affected · git
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before a14b56863348686dd0387eea8ce66b85cf455908affected · git
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before 13a66ca1e235d4bcd53d12d4c68490cad7f8e46faffected · git
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before 3a2999704ac36cfb4041fed3652d26a3373e8d12affected · git
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before 4fd258e281fa8bc15e9ce2c7691941537e9258adaffected · git
    • c865e5d99e25a171e8262fc0f7ba608568633c64 and later · before d64cb81dcbd54927515a7f65e5e24affdc73c14baffected · git
    • before 2.6.16not affected · semver
    • 6.1.191 and later · up to and including 6.1.*not affected · semver
    • 6.6.134 and later · up to and including 6.6.*not affected · semver
Affected versions · NVD (5)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel2.6.16 and later · before 6.6.134
  • linux linux kernel6.7 and later · before 6.12.81
  • linux linux kernel6.13 and later · before 6.18.22
  • linux linux kernel6.19 and later · before 6.19.12
  • linux linux kernel7.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxfrom 0—
Debian:13linuxbefore 6.12.85-16.12.85-1
Debian:14linuxbefore 6.19.12-16.19.12-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-31673Apr 25, 2026 · af_unix: read UNIX_DIAG_VFS data under unix_state_lock
    31Monitor
  • ← EarlierCVE-2026-31674Apr 25, 2026 · netfilter: ip6t_rt: reject oversized addrnr in rt_mt6_check()
    28Monitor
  • Later →CVE-2026-31676Apr 25, 2026 · rxrpc: only handle RESPONSE during service challenge
    30Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux13a66ca1e235d4bcd53d12d4c68490cad7f8e46fVendor (CNA)
Linux Linux3a2999704ac36cfb4041fed3652d26a3373e8d12Vendor (CNA)
Linux Linux4fd258e281fa8bc15e9ce2c7691941537e9258adVendor (CNA)
Linux Linux8d3de49c22ec0ec8f7199cc7e2b0559de7306f87Vendor (CNA)
Linux Linuxa14b56863348686dd0387eea8ce66b85cf455908Vendor (CNA)
Linux Linuxd64cb81dcbd54927515a7f65e5e24affdc73c14bVendor (CNA)
azl3 kernel 6.6.130.1-3 on Azure Linux 3.06.6.134.1-2 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.12.85-1 · Debian:13Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records