Vulnerability · CVE-2025-39852
In the Linux kernel, the following vulnerability has been resolved: net/tcp: Fix socket memory leak in TCP-AO failure handling for IPv6 When tcp_ao_copy_all_matching() fails in tcp
Published Sep 19, 2025 · catalog updated May 11, 2026 · Linux Linux
Check if you run it
No confirmed exploitation is on record for CVE-2025-39852. EPSS is 0.15%. Act only if a listed version of Linux Linux is installed.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium5.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.15%
- Remediation
- Vendor / distro source
- Affected products
- vendor Linux Linux patch: 0
In the Linux kernel, the following vulnerability has been resolved: net/tcp: Fix socket memory leak in TCP-AO failure handling for IPv6 When tcp_ao_copy_all_matching() fails in tcp_v6_syn_recv_sock() it just exits the function. This ends up causing a memory-leak: unreferenced object 0xffff0000281a8200 (size 2496): comm "softirq", pid 0, jiffies 4295174684 hex dump (first 32 bytes): 7f 00 00 06 7f 00 00 06 00 00 00 00 cb a8 88 13 ................ 0a 00 03 61 00 00 00 00 00 00 00 00 00 00 00 00 ...a............ backtrace (crc 5ebdbe15): kmemleak_alloc+0x44/0xe0 kmem_cache_alloc_noprof+0x248/0x47
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Linux Linux patch: 0patch: 0
How to fix CVE-2025-39852
Recommended remediation
A vendor or distribution source is linked. Check that advisory for patch availability; this catalog does not invent fix status.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-39852. EPSS is 0.15%. Act only if a listed version of Linux Linux is installed.
Which versions are affected?
Compare what you have installed with Linux Linux patch: 0 patch: 0. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.15%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Sep 19, 2025 · EUVD
Detected
In the Linux kernel, the following vulnerability has been resolved: net/tcp: Fix socket memory leak in TCP-AO failure handling for IPv6 When tcp_ao_copy_all_matching() fails in tcp_v6_syn_recv_sock() it just exits the function. This ends up causing a memory-leak: unreferenced object 0xffff0000281a8200 (size 2496): comm "softirq", pid 0, jiffies 4295174684 hex dump (first 32 bytes): 7f 00 00 06 7f
May 11, 2026 · EUVD
Updated
In the Linux kernel, the following vulnerability has been resolved: net/tcp: Fix socket memory leak in TCP-AO failure handling for IPv6 When tcp_ao_copy_all_matching() fails in tcp_v6_syn_recv_sock() it just exits the function. This ends up causing a memory-leak: unreferenced object 0xffff0000281a8200 (size 2496): comm "softirq", pid 0, jiffies 4295174684 hex dump (first 32 bytes): 7f 00 00 06 7f
Sources
- CVE.orgVulnerability recordCVE-2025-39852
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-39852
30-day exploitation probability 0.15%
first.org - EUVDVulnerability recordEUVD-2025-30348
In the Linux kernel, the following vulnerability has been resolved: net/tcp: Fix socket memory leak in TCP-AO failure handling for IPv6 When tcp_ao_copy_all_matching() fails in tcp_v6_syn_recv_sock() it just exits the function. This ends up causing a memory-leak: unreferenced obj
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 23, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.