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NVD / CVE Program· CNA Linux

CVE-2023-52527: ipv4, ipv6: Fix handling of transhdrlen in __ip{,6}_append_data()

MediumCVSS 5.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • 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: 0.23% (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 1fc793d68d50dee4782ef2e808913d5dd880bcc6, 559d697c5d072593d22b3e0bd8b8081108aeaf59, 7626b9fed53092aa2147978070e610ecb61af844.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 1fc793d68d50dee4782ef2e808913d5dd880bcc6, 559d697c5d072593d22b3e0bd8b8081108aeaf59, 7626b9fed53092aa2147978070e610ecb61af844 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: ipv4, ipv6: Fix handling of transhdrlen in __ip{,6}_append_data() Including the transhdrlen in length is a problem when the packet is partially filled (e.g. something like send(MSG_MORE) happened previously) when appending to an IPv4 or IPv6 packet as we don't want to repeat the transport header or account for it twice. This can happen under some circumstances, such as splicing into an L2TP socket. The symptom observed is a warning in __ip6_append_data(): WARNING: CPU: 1 PID: 5042 at net/ipv6/ip6_output.c:1800 __ip6_append_data.isra.0+0x1be8/0x47f0 net/ipv6/ip6_output.c:1800 that occurs when MSG_SPLICE_PAGES is used to append more data to an already partially occupied skbuff. The warning occurs when 'copy' is larger than the amount of data in the message iterator. This is because the requested length includes the transport header length when it shouldn't. This can be triggered by, for example: sfd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_L2TP); bind(sfd, ...); // ::1 connect(sfd, ...); // ::1 port 7 send(sfd, buffer, 4100, MSG_MORE); sendfile(sfd, dfd, NULL, 1024); Fix this by only adding transhdrlen into the length if the write queue is empty in l2tp_ip6_sendmsg(), analogously to how UDP does things. l2tp_ip_sendmsg() looks like it won't suffer from this problem as it builds the UDP packet itself.

Published
Mar 2, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 15th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
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

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Follow CVE-2023-52527

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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

    • 3.5affected
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before 7626b9fed53092aa2147978070e610ecb61af844affected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before 559d697c5d072593d22b3e0bd8b8081108aeaf59affected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before 1fc793d68d50dee4782ef2e808913d5dd880bcc6affected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before 96b2e1090397217839fcd6c9b6d8f5d439e705edaffected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before cd1189956393bf850b2e275e37411855d3bd86bbaffected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before f6a7182179c0ed788e3755ee2ed18c888ddcc33faffected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before fe80658c08e3001c80c5533cd41abfbb0e0e28fdaffected · git
    • a32e0eec7042b21ccb52896cf715e3e2641fed93 and later · before 9d4c75800f61e5d75c1659ba201b6c0c7ead3070affected · git
    • before 3.5not affected · semver
Affected versions · NVD (8)

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

  • linux linux kernel3.5 and later · before 4.14.327
  • linux linux kernel4.15 and later · before 4.19.296
  • linux linux kernel4.20 and later · before 5.4.258
  • linux linux kernel5.5 and later · before 5.10.198
  • linux linux kernel5.11 and later · before 5.15.135
  • linux linux kernel5.16 and later · before 6.1.57
  • linux linux kernel6.2 and later · before 6.5.7
  • linux linux kernel6.6

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.64-16.1.64-1
Debian:13linuxbefore 6.5.8-16.5.8-1

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-2023-52525Mar 2, 2024 · wifi: mwifiex: Fix oob check condition in mwifiex_process_rx_packet
    28Monitor
  • ← EarlierCVE-2023-52526Mar 2, 2024 · erofs: fix memory leak of LZMA global compressed deduplication
    22Monitor
  • Later →CVE-2023-52528Mar 2, 2024 · net: usb: smsc75xx: Fix uninit-value access in __smsc75xx_read_reg
    22Monitor

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 Linux1fc793d68d50dee4782ef2e808913d5dd880bcc6Vendor (CNA)
Linux Linux559d697c5d072593d22b3e0bd8b8081108aeaf59Vendor (CNA)
Linux Linux7626b9fed53092aa2147978070e610ecb61af844Vendor (CNA)
Linux Linux96b2e1090397217839fcd6c9b6d8f5d439e705edVendor (CNA)
Linux Linux9d4c75800f61e5d75c1659ba201b6c0c7ead3070Vendor (CNA)
Linux Linuxcd1189956393bf850b2e275e37411855d3bd86bbVendor (CNA)
Linux Linuxf6a7182179c0ed788e3755ee2ed18c888ddcc33fVendor (CNA)
Linux Linuxfe80658c08e3001c80c5533cd41abfbb0e0e28fdVendor (CNA)
debian:linux6.1.64-1 · Debian:12Package 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.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

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

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/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.

References

Show all references (7 more)

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

All records