CVE-2026-52935: xfrm: espintcp: do not reuse an in-progress partial send
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: 0.09% (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 1777ceac4bea5e568a5ad44b7f9bb219c1db21b6, 37487d55bf3300e3d2c1368da5c2bd3e3834ea4f, 6564e9c7af7e1dc7bfe7f3093b728abe484d7630; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 1777ceac4bea5e568a5ad44b7f9bb219c1db21b6, 37487d55bf3300e3d2c1368da5c2bd3e3834ea4f, 6564e9c7af7e1dc7bfe7f3093b728abe484d7630; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1 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: xfrm: espintcp: do not reuse an in-progress partial send espintcp keeps a single in-flight transmit in ctx->partial. Before building a new sk_msg, espintcp_sendmsg() first tries to flush that state through espintcp_push_msgs(). For blocking callers, espintcp_push_msgs() may return success even when the previous partial send is still pending. espintcp_sendmsg() would then reinitialize emsg->skmsg and reuse ctx->partial while the old transfer still owns that state. Do not rebuild the send message when ctx->partial is still in progress. If espintcp_push_msgs() returns with emsg->len still set, fail the new send instead of overwriting the live partial state. This is a memory-safety fix: reusing the live partial-send state can leave a stale offset attached to a new sk_msg and lead to an out-of- bounds read in the send path. tcp_sendmsg_locked() already handles waiting for send buffer memory, so the fix here is just to preserve espintcp's one-message-at-a-time transmit state.
- Published
- Jun 24, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.0% · 0th percentile
- CWE
- CWE-787
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.0%
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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel5.6 and later · before 5.10.259
- linux linux kernel5.11 and later · before 5.15.210
- linux linux kernel5.16 and later · before 6.1.176
- linux linux kernel6.2 and later · before 6.6.143
- linux linux kernel6.7 and later · before 6.12.94
- linux linux kernel6.13 and later · before 6.18.36
- linux linux kernel6.19 and later · before 7.0.13
- linux linux kernel7.1
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
- 5.6affected
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before 6564e9c7af7e1dc7bfe7f3093b728abe484d7630affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before 1777ceac4bea5e568a5ad44b7f9bb219c1db21b6affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before 8c6c691bf062dc0753a139a4ab8cb92a70fcf8f3affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before aa82a078f70f7ff88ba7d1017134e79d1ac140f2affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before ba21439302db9a82fe4edbed1e38a97271529421affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before f9b38a8fbfa07f1deaf7ee1eb38fa8b21ea13990affected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before 37487d55bf3300e3d2c1368da5c2bd3e3834ea4faffected · git
- e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 and later · before c381039ade2e161ab08c0eda73c4f8b9a7115928affected · git
- before 5.6not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | kernel | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel-matched | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-extra | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel-matched | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-extra | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-abi-stablelists | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-cross-headers | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel-matched | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules-core | before 6.12.0-211.67.1.el10_2 | 6.12.0-211.67.1.el10_2 |
+96
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- 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 KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2026-52931Jun 24, 2026 · batman-adv: tp_meter: avoid use of uninit sender vars39Monitor
- ← EarlierCVE-2026-52933Jun 24, 2026 · io_uring/poll: fix signed comparison in io_poll_get_ownership()31Monitor
- Later →CVE-2026-52936Jun 24, 2026 · crypto: jitterentropy - replace long-held spinlock with mutex22Monitor
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 | 1777ceac4bea5e568a5ad44b7f9bb219c1db21b6 | Vendor (CNA) |
| Linux Linux | 37487d55bf3300e3d2c1368da5c2bd3e3834ea4f | Vendor (CNA) |
| Linux Linux | 6564e9c7af7e1dc7bfe7f3093b728abe484d7630 | Vendor (CNA) |
| Linux Linux | 8c6c691bf062dc0753a139a4ab8cb92a70fcf8f3 | Vendor (CNA) |
| Linux Linux | aa82a078f70f7ff88ba7d1017134e79d1ac140f2 | Vendor (CNA) |
| Linux Linux | ba21439302db9a82fe4edbed1e38a97271529421 | Vendor (CNA) |
| Linux Linux | c381039ade2e161ab08c0eda73c4f8b9a7115928 | Vendor (CNA) |
| Linux Linux | f9b38a8fbfa07f1deaf7ee1eb38fa8b21ea13990 | Vendor (CNA) |
| azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 | 6.6.143.1-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:bpftool | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-core | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-core | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel-matched | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-core | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-extra | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel-matched | 6.12.0-211.67.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-abi-stablelists | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-core | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-cross-headers | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-core | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-devel | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-modules | 4.18.0-553.176.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
+18
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 researchersFinders, 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.
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).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0440 · Jun 25, 2026(Linux Kernel Güvenlik Bildirimi)
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-787 · Out-of-bounds WriteCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
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— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- git.kernel.org/stable/c/37487d55bf3300e3d2c1368da5c2bd3e3834ea4f
- git.kernel.org/stable/c/6564e9c7af7e1dc7bfe7f3093b728abe484d7630
- git.kernel.org/stable/c/8c6c691bf062dc0753a139a4ab8cb92a70fcf8f3
- git.kernel.org/stable/c/aa82a078f70f7ff88ba7d1017134e79d1ac140f2
- git.kernel.org/stable/c/ba21439302db9a82fe4edbed1e38a97271529421
- git.kernel.org/stable/c/c381039ade2e161ab08c0eda73c4f8b9a7115928
- git.kernel.org/stable/c/f9b38a8fbfa07f1deaf7ee1eb38fa8b21ea13990
Vendor advisories and official records. Exploit/PoC links are deliberately left out.