NVD / CVE Program· CNA Linux

CVE-2026-68335: rds: drop incoming messages that cross network namespace boundaries

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: 0.13% (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 03c574112e5d066df0ddce36d7438e850bcf3050, 0f8690e3869109cd5803ccb400889d20a0b54e0e, 1e2e2d9806944fe485824d617c8b7c78116c22db; azl3 kernel 6.6.143.1-1 on Azure Linux 3.0 6.6.150.1-1.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 03c574112e5d066df0ddce36d7438e850bcf3050, 0f8690e3869109cd5803ccb400889d20a0b54e0e, 1e2e2d9806944fe485824d617c8b7c78116c22db; azl3 kernel 6.6.143.1-1 on Azure Linux 3.0 6.6.150.1-1 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: rds: drop incoming messages that cross network namespace boundaries rds_find_bound() looks up the destination socket using a global rhashtable keyed solely on (addr, port, scope_id). Network namespaces are not part of the key, so a sender in netns A can deliver an incoming message (inc) to a socket that lives in a different netns B. When this happens, inc->i_conn points to an rds_connection whose c_net is netns A, but the receiving rs lives in netns B. Once the child process that created netns A exits, cleanup_net() calls rds_loop_exit_net() -> rds_loop_kill_conns() -> rds_conn_destroy(), freeing that connection. If the survivor socket in netns B still holds the inc, any subsequent dereference of inc->i_conn is a use-after-free. There are two dangerous sites in rds_clear_recv_queue(): 1. inc->i_conn->c_lcong (offset 88 of freed rds_connection, size 200) read via rds_recv_rcvbuf_delta() -- confirmed by KASAN. 2. inc->i_conn->c_trans->inc_free(inc) (function pointer at offset 80) called via rds_inc_put() when the inc refcount reaches zero -- same race window, potential call-through-freed-object primitive. The bug is reachable from unprivileged user namespaces (CLONE_NEWUSER + CLONE_NEWNET), available since Linux 3.8. Fix this by rejecting the delivery in rds_recv_incoming() when the socket returned by rds_find_bound() belongs to a different network namespace than the connection that carried the message. Use the existing rds_conn_net() / sock_net() helpers and net_eq() for the comparison.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Aug 10, 2026
Updated: Oct 19, 2026
EPSS: 0.1% · 3th percentile
CWE: CWE-416

Report tools

JSON

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
- c827073c95fde388bc65fe5227f944eaf859b9f0, 4.18affected
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 742ff6f02545212e991cd8b45011e40d2c2ef25aaffected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before abff41fd928328bbf3dda1140beb2e61fa424ccdaffected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 03c574112e5d066df0ddce36d7438e850bcf3050affected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 1e2e2d9806944fe485824d617c8b7c78116c22dbaffected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before cfb3ce07b705e486e022a2f2b1242b48f13981ffaffected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 9591042533140dfe6608d9344806d567dcd39d02affected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 0f8690e3869109cd5803ccb400889d20a0b54e0eaffected · git
- c809195f5523dd4d09403bbb1c9732d548aa0d1e and later · before 5521ae71e32a8069ed4ca6e792179dc57bc43ab2affected · git
- 4.17.19 and later · before 4.18affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.187-1	6.1.187-1
Debian:12	linux-6.12	before 6.12.101-1~deb12u1	6.12.101-1~deb12u1
Debian:13	linux	before 6.12.101-1	6.12.101-1
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
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CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
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Published before and after this one in the same product

← EarlierCVE-2026-68328Aug 10, 2026 · nfp: Check resource mutex allocation
0Monitor
← EarlierCVE-2026-68329Aug 10, 2026 · iommu/amd: Wait for completion instead of returning early in iommu_completion_wait()
35Monitor
Later →CVE-2026-68336Aug 10, 2026 · bonding: fix devconf_all NULL dereference when IPv6 is disabled
0Monitor

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	03c574112e5d066df0ddce36d7438e850bcf3050	Vendor (CNA)
Linux Linux	0f8690e3869109cd5803ccb400889d20a0b54e0e	Vendor (CNA)
Linux Linux	1e2e2d9806944fe485824d617c8b7c78116c22db	Vendor (CNA)
Linux Linux	4.18	Vendor (CNA)
Linux Linux	5521ae71e32a8069ed4ca6e792179dc57bc43ab2	Vendor (CNA)
Linux Linux	742ff6f02545212e991cd8b45011e40d2c2ef25a	Vendor (CNA)
Linux Linux	9591042533140dfe6608d9344806d567dcd39d02	Vendor (CNA)
Linux Linux	abff41fd928328bbf3dda1140beb2e61fa424ccd	Vendor (CNA)
Linux Linux	cfb3ce07b705e486e022a2f2b1242b48f13981ff	Vendor (CNA)
azl3 kernel 6.6.143.1-1 on Azure Linux 3.0	6.6.150.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
debian:linux	6.1.187-1 · Debian:12	Package registry (OSV)
debian:linux-6.12	6.12.101-1~deb12u1 · Debian:12	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-2026-681170 days aparttipc: clear sock->sk on the failed-insert path in tipc_sk_create()
39Monitor
CVE-2026-681270 days apartila: reload IPv6 header after pskb_may_pull in checksum adjust
39Monitor
CVE-2026-681440 days apartphonet: pep: fix use-after-free in pep_get_sb()
39Monitor
CVE-2026-681560 days apartlibceph: refresh auth->authorizer_buf{,_len} after authorizer update
39Monitor
CVE-2026-683810 days apartksmbd: pin conn during async oplock break notification
39Monitor
CVE-2026-684260 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.

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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-26-0800 · Aug 11, 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, 10:07 PM UTC

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

References

git.kernel.org/stable/c/03c574112e5d066df0ddce36d7438e850bcf3050

Show all references (7 more)

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

All records