Unknown

CVE-2026-80848 — xfrm: espintcp: fix UAF during close

In the Linux kernel, the following vulnerability has been resolved: xfrm: espintcp: fix UAF during close ZDI reported and analyzed a race condition during close for espintcp sockets: espintcp_close() frees emsg->skb via kfree_skb() without holding any socket lock. Concurrently, the xfrm_trans_reinject work queue invokes esp_output_tcp_finish() -> espintcp_push_skb() -> espintcp_push_msgs() -> skb_send_sock_locked(), which reads the same skb as a data source. Fix this by adding a synchronize_rcu() call after resetting sk_prot, since esp_output_tcp_finish() runs under RCU and won't use a socket with sk_prot == &tcp_prot. Simply taking the socket lock in espintcp_close() could lead to leaks, if esp_output_tcp_finish() re-adds an skb in the slot we just freed. After this, the existing barrier() is no longer needed.

Published Sep 4, 2026 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.2%

ahead of 9% of scored CVEs · Oct 26, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < 29121c5e6591da527e8e36ddac7120dc527f574d≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < ed5d9102190c45fc70121c036b0626b740040b75≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < 4bc0dfa28dca6fc0084203732695968049c44072≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < ff8dd7a932f34409a56e1b91a1219340f17457e9≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < 4b31a875693c480c611519faca46216514e3e052≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < 24efebecf415ba264adba0f0491cec436463a14f≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < eb3bbf29c723fe75c0eb92be14f0ec92971fe272≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < 54b41ad14da9a981131ab6e4d3f79321a503ea5d and 2 more ≥ e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and < deb232e884877bf10b4ce2580909eedec986c284version 5.6	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 26, 2026 · 11 reading(s) · max 0.20%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 4, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 19, 2026 – Oct 19, 2026
1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

11 on the record

git.kernel.org/stable/c/54b41ad14da9a981131ab6e4d3f79321a503ea5d
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-80848
GitHub Security Advisories
git.kernel.org/stable/c/eb3bbf29c723fe75c0eb92be14f0ec92971fe272
NIST National Vulnerability Database
github.com/advisories/GHSA-gvv5-3h67-3922
GitHub Security Advisories
git.kernel.org/stable/c/4bc0dfa28dca6fc0084203732695968049c44072
NIST National Vulnerability Database
git.kernel.org/stable/c/24efebecf415ba264adba0f0491cec436463a14f
NIST National Vulnerability Database
git.kernel.org/stable/c/deb232e884877bf10b4ce2580909eedec986c284
NIST National Vulnerability Database
git.kernel.org/stable/c/29121c5e6591da527e8e36ddac7120dc527f574d
NIST National Vulnerability Database
git.kernel.org/stable/c/4b31a875693c480c611519faca46216514e3e052
NIST National Vulnerability Database
git.kernel.org/stable/c/ff8dd7a932f34409a56e1b91a1219340f17457e9
NIST National Vulnerability Database
git.kernel.org/stable/c/ed5d9102190c45fc70121c036b0626b740040b75
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 23h
Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 23h
Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 23h
Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 23h
Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 23h
Unknown CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 23h

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-80848 is "xfrm: espintcp: fix UAF during close", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.20% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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