NVD / CVE Program· CNA Linux

CVE-2026-64575: bpf: tcp: fix double sock release on batch realloc

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: 0.15% (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 7a6a6d2a127866935f87b55b557bc89693065462, 8a726e9585ffe7bfbfad2b5279277a00973970f3, 980a813452754f8001704744e92f7aa697c53dd3.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 7a6a6d2a127866935f87b55b557bc89693065462, 8a726e9585ffe7bfbfad2b5279277a00973970f3, 980a813452754f8001704744e92f7aa697c53dd3 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: bpf: tcp: fix double sock release on batch realloc bpf_iter_tcp_batch() releases the current batch via bpf_iter_tcp_put_batch(), which drops the socket refs and rewrites each slot with the socket cookie, then grows the batch. cur_sk/end_sk are kept for bpf_iter_tcp_resume(), but on realloc failure the function returns ERR_PTR() before resume runs, leaving cur_sk < end_sk over slots that now hold cookies rather than sock pointers. bpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and dereferences a cookie as a struct sock. Empty the batch on the failure path so stop() does not release it again. The sockets were already freed by the first bpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans the bucket from the start instead of skipping it. The sibling GFP_NOWAIT failure path still holds real socket references and is left for stop() to release. BUG: KASAN: null-ptr-deref in __sock_gen_cookie Read of size 8 at addr 0000000000000059 by task exploit ... __sock_gen_cookie (net/core/sock_diag.c:28) bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918) bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270) bpf_seq_read (kernel/bpf/bpf_iter.c:205) vfs_read (fs/read_write.c:572) ksys_read (fs/read_write.c:716) do_syscall_64 entry_SYSCALL_64_after_hwframe Kernel panic - not syncing: Fatal exception

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Aug 5, 2026
Updated: Oct 19, 2026
EPSS: 0.1% · 4th percentile
CWE: CWE-416

Report tools

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Action score

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.

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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.

—

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
- 6.17affected
- 9794ac757a650dd594391192183c9caf939f8223 and later · before c842882e4c5d2818b858d6baf3fd10958c93f729affected · git
- 1d7a82c1df5fc397eaca9c6b8c8f61aae9866ad4 and later · before 7a6a6d2a127866935f87b55b557bc89693065462affected · git
- 36f955807ee4ede07e9410772f792e4cb4ec807b and later · before f0c1810320b0dac228103fad7311e89532134d83affected · git
- cdec67a489d4fdae3e83e04fca0419136a83c4c2 and later · before 9f27c4f0ae35b5390ce4f7a54d3501144e41a54daffected · git
- cdec67a489d4fdae3e83e04fca0419136a83c4c2 and later · before 8a726e9585ffe7bfbfad2b5279277a00973970f3affected · git
- cdec67a489d4fdae3e83e04fca0419136a83c4c2 and later · before 980a813452754f8001704744e92f7aa697c53dd3affected · git
- before 6.17not affected · semver
- 6.18.42 and later · up to and including 6.18.*not affected · semver
- 7.1.6 and later · up to and including 7.1.*not affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:14	linux	before 7.1.6-1	7.1.6-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
40Plan
CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
40Plan
CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
40Plan

Published before and after this one in the same product

← EarlierCVE-2026-64571Aug 5, 2026 · wifi: p54: validate RX frame length in p54_rx_eeprom_readback()
0Monitor
← EarlierCVE-2026-64574Aug 5, 2026 · wifi: mac80211: tear down new links on vif update error path
31Monitor
Later →CVE-2026-64576Aug 5, 2026 · nexthop: initialize extack in nh_res_bucket_migrate()
28Monitor

Remediation

Which version to upgrade to

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

Product / package	Fixed version	Source
Linux Linux	7a6a6d2a127866935f87b55b557bc89693065462	Vendor (CNA)
Linux Linux	8a726e9585ffe7bfbfad2b5279277a00973970f3	Vendor (CNA)
Linux Linux	980a813452754f8001704744e92f7aa697c53dd3	Vendor (CNA)
Linux Linux	9f27c4f0ae35b5390ce4f7a54d3501144e41a54d	Vendor (CNA)
Linux Linux	c842882e4c5d2818b858d6baf3fd10958c93f729	Vendor (CNA)
Linux Linux	f0c1810320b0dac228103fad7311e89532134d83	Vendor (CNA)
debian:linux	7.1.6-1 · Debian:14	Package 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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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.

No credits in the CNA record.

Variant candidates

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

CVE-2026-645641 days apartsctp: don't free the ASCONF's own transport in DEL-IP processing
39Monitor
CVE-2026-681175 days aparttipc: clear sock->sk on the failed-insert path in tipc_sk_create()
39Monitor
CVE-2026-681275 days apartila: reload IPv6 header after pskb_may_pull in checksum adjust
39Monitor
CVE-2026-681445 days apartphonet: pep: fix use-after-free in pep_get_sb()
39Monitor
CVE-2026-683815 days apartksmbd: pin conn during async oplock break notification
39Monitor
CVE-2026-684265 days apartxfrm: fix stale skb->prev after async crypto steals a GSO segment
39Monitor

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

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

TR-26-0742 · Aug 5, 2026(Linux Kernel Güvenlik Bildirimi)

All national notices →

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-416 · Use After Free

CVSS vector

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

nvd-secondary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

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

SSVC exploitation— → noneOct 16, 2026, 5:07 PM UTC
Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

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

References

git.kernel.org/stable/c/7a6a6d2a127866935f87b55b557bc89693065462

Show all references (5 more)

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

All records