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Noroxi
NVD / CVE Program· CNA XEN

CVE-2023-46838: Linux: netback processing of zero-length transmit fragment

Noroxi assessment

Priority: Monitor (action score 30/100)

  • 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: 1.1% (FIRST EPSS); higher than 67.8% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: linux-lts (Alpine:v3.16) 5.15.147-r1; linux-lts (Alpine:v3.18) 6.1.74-r0; linux-lts (Alpine:v3.21) 6.6.13-r1.

Low priority for now. Upgrade to linux-lts (Alpine:v3.16) 5.15.147-r1; linux-lts (Alpine:v3.18) 6.1.74-r0; linux-lts (Alpine:v3.21) 6.6.13-r1 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

Transmit requests in Xen's virtual network protocol can consist of multiple parts. While not really useful, except for the initial part any of them may be of zero length, i.e. carry no data at all. Besides a certain initial portion of the to be transferred data, these parts are directly translated into what Linux calls SKB fragments. Such converted request parts can, when for a particular SKB they are all of length zero, lead to a de-reference of NULL in core networking code.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Jan 29, 2024
Updated
Jun 17, 2026
EPSS
1.1% · 67th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.1%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

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-2023-46838

When you'll hear from us

  • when it enters CISA KEV
  • 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
fedoraprojectfedora
debiandebian linux

Affected versions

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

  • debian debian linux10.0
  • fedoraproject fedora38
  • fedoraproject fedora39
  • linux linux kernel5.11 and later · before 5.15.148
  • linux linux kernel5.16 and later · before 6.1.75
  • linux linux kernel4.14 and later · before 4.19.306
  • linux linux kernel6.7 and later · before 6.7.2
  • linux linux kernel6.2 and later · before 6.6.14
  • linux linux kernel4.20 and later · before 5.4.268
  • linux linux kernel5.5 and later · before 5.10.209

Versions reported by the vendor

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

  • Linux Linux

    • consult Xen advisory XSA-448unknown

Package-level exposure

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

EcosystemPackageAffected rangeFix
Alpine:v3.16linux-ltsbefore 5.15.147-r15.15.147-r1
Alpine:v3.18linux-ltsbefore 6.1.74-r06.1.74-r0
Alpine:v3.21linux-ltsbefore 6.6.13-r16.6.13-r1
Debian:10linuxbefore 4.19.316-14.19.316-1
Debian:10linux-5.10before 5.10.209-2~deb10u15.10.209-2~deb10u1
Debian:12linuxbefore 6.1.76-16.1.76-1
Debian:13linuxbefore 6.6.15-16.6.15-1
openSUSE:Leap 15.5dtb-aarch64before 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-64kbbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-azurebefore 5.14.21-150500.33.34.15.14.21-150500.33.34.1
openSUSE:Leap 15.5kernel-debugbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-defaultbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-default-basebefore 5.14.21-150500.55.49.1.150500.6.21.25.14.21-150500.55.49.1.150500.6.21.2
openSUSE:Leap 15.5kernel-docsbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-kvmsmallbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-obs-buildbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-obs-qabefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-rtbefore 5.14.21-150500.13.35.15.14.21-150500.13.35.1
openSUSE:Leap 15.5kernel-rt_debugbefore 5.14.21-150500.13.35.15.14.21-150500.13.35.1
openSUSE:Leap 15.5kernel-sourcebefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-source-azurebefore 5.14.21-150500.33.34.15.14.21-150500.33.34.1
openSUSE:Leap 15.5kernel-source-rtbefore 5.14.21-150500.13.35.15.14.21-150500.13.35.1
openSUSE:Leap 15.5kernel-symsbefore 5.14.21-150500.55.49.15.14.21-150500.55.49.1
openSUSE:Leap 15.5kernel-syms-azurebefore 5.14.21-150500.33.34.15.14.21-150500.33.34.1

+65

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-2023-6200Jan 28, 2024 · Kernel: icmpv6 router advertisement packets, aka linux tcp/ip remote code execution vulnerability
    31Monitor
  • ← EarlierCVE-2024-0841Jan 28, 2024 · Kernel: hugetlbfs: null pointer dereference in hugetlbfs_fill_super function
    31Monitor
  • Later →CVE-2024-21803Jan 30, 2024 · Possible UAF in bt_accept_poll in Linux kernel
    31Monitor

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
alpine:linux-lts5.15.147-r1 · Alpine:v3.16Package registry (OSV)
debian:linux6.1.76-1 · Debian:12Package registry (OSV)
debian:linux-5.105.10.209-2~deb10u1 · Debian:10Package registry (OSV)
opensuse:dtb-aarch645.14.21-150500.55.49.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-64kb5.14.21-150500.55.49.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-azure5.14.21-150500.33.34.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-debug5.14.21-150500.55.49.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-default5.14.21-150400.24.108.1 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-default-base5.14.21-150400.24.108.1.150400.24.50.2 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-rt5.14.21-150500.13.35.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-rt_debug5.14.21-150500.13.35.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-source-azure5.14.21-150500.33.34.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-source-rt5.14.21-150500.13.35.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-syms-azure5.14.21-150500.33.34.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-syms-rt5.14.21-150500.13.35.1 · openSUSE:Leap 15.5Package registry (OSV)
suse:kernel-64kb5.3.18-150300.59.150.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-azure5.14.21-150500.33.34.1 · SUSE:Linux Enterprise Module for Public Cloud 15 SP5Package registry (OSV)
suse:kernel-default5.3.18-150300.59.150.1 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)
suse:kernel-default-base5.3.18-150300.59.150.1.150300.18.88.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-docs5.3.18-150300.59.150.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP3_Update_411-150300.7.3.1 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)
suse:kernel-livepatch-SLE15-SP4-RT_Update_181-150400.1.3.1 · SUSE:Linux Enterprise Live Patching 15 SP4Package registry (OSV)
suse:kernel-livepatch-SLE15-SP5-RT_Update_101-150500.11.5.1 · SUSE:Linux Enterprise Live Patching 15 SP5Package registry (OSV)
suse:kernel-obs-build5.3.18-150300.59.150.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-preempt5.3.18-150300.59.150.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-rt5.14.21-150500.13.35.1 · SUSE:Linux Enterprise Micro 5.5Package registry (OSV)
suse:kernel-rt5.3.18-150300.158.1 · SUSE:Linux Enterprise Micro 5.1Package registry (OSV)
suse:kernel-rt_debug4.12.14-10.162.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-rt_debug5.14.21-150500.13.35.1 · SUSE:Real Time Module 15 SP5Package registry (OSV)
suse:kernel-source-azure5.14.21-150500.33.34.1 · SUSE:Linux Enterprise Module for Public Cloud 15 SP5Package registry (OSV)

+4

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.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-476 · NULL Pointer Dereference

CVSS vector

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

nvd-primary

Attack context

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

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

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

All records