CVE-2026-68302: amt: re-read skb header pointers after every pull
Noroxi assessment
Priority: Monitor (action score 39/100)
- 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: 0.47% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 3656a79f94c471827a08f2cacce5f94ad5e52c24, 37ff890f9c18dfbcf57e17199901d4fd1e4c174e, 7746d588d42a4ac0117b68ed8e9b22a9da53dfb7; 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 3656a79f94c471827a08f2cacce5f94ad5e52c24, 37ff890f9c18dfbcf57e17199901d4fd1e4c174e, 7746d588d42a4ac0117b68ed8e9b22a9da53dfb7; 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: amt: re-read skb header pointers after every pull Several AMT receive and transmit paths cache a pointer into the skb head (ip_hdr(), ipv6_hdr(), eth_hdr() or the AMT message header) and then call a helper that can reallocate that head before the cached pointer is used again. pskb_may_pull(), ip_mc_may_pull(), ipv6_mc_may_pull(), iptunnel_pull_header(), ip_mc_check_igmp() and ipv6_mc_check_mld() can all free the old head and move the data, so a pointer taken before the call dangles afterwards and the later access is a use-after-free of the freed head. The affected sites are: amt_rcv() caches ip_hdr() before amt_parse_type() pulls, then reads iph->saddr. amt_dev_xmit() caches ip_hdr()/ipv6_hdr() before ip_mc_check_igmp()/ ipv6_mc_check_mld() and pskb_may_pull(), then reads the group address. amt_multicast_data_handler() caches eth_hdr() before pskb_may_pull(), then writes the L2 header. amt_membership_query_handler() caches the AMT header, the outer and inner eth_hdr() and ip_hdr() before iptunnel_pull_header() and several pulls, then reads and writes them. amt_igmpv3_report_handler() and amt_mldv2_report_handler() cache ip_hdr()/ipv6_hdr() and the current group record and read the record count from the report header inside the record loop, across the *_mc_may_pull() calls. amt_update_handler() caches ip_hdr() and the AMT membership-update header before pskb_may_pull(), iptunnel_pull_header(), ip_mc_check_igmp() and the report handler, then reads iph->daddr and amtmu->nonce / amtmu->response_mac. Fix each site by either snapshotting the scalar that is used after the pull before the first pull runs, or re-deriving the header pointer from the skb after the last pull that can move the head. Values that are stable across the pull (source and group address, the response MAC and nonce, the record count, the outer source MAC) are snapshotted; pointers that are written through or read repeatedly are re-derived.
- Published
- Aug 10, 2026
- Updated
- Aug 19, 2026
- EPSS
- 0.4% · 41th percentile
- CWE
- —
Report tools
Action score
39
Monitor
Low priority for now.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.4%
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 9.8
- 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.
—
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
- 5.16affected
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before 37ff890f9c18dfbcf57e17199901d4fd1e4c174eaffected · git
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before 9005b221cb1f9c3c1a2ef656fb0e8fa80c0a187eaffected · git
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before 7746d588d42a4ac0117b68ed8e9b22a9da53dfb7affected · git
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before ca0e8b661957f777591efe874cd9d9a63619cd99affected · git
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before 7f48e3ddad8e97545b25788b8203b3a539df1621affected · git
- cbc21dc1cfe949e37b2a54c71511579f1899e8d4 and later · before 3656a79f94c471827a08f2cacce5f94ad5e52c24affected · git
- before 5.16not affected · semver
- 6.1.183 and later · up to and including 6.1.*not affected · semver
- 6.6.148 and later · up to and including 6.6.*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: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 recordsOther highest-scoring records for the same primary product.
- CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation40Plan
- CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment40Plan
- CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()40Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-68296Aug 10, 2026 · net: gre: fix lltx regression for GRE tunnels with SEQ/CSUM0Monitor
- ← EarlierCVE-2026-68301Aug 10, 2026 · net: hsr: fix memory leak on slave unregistration by removing synced VLANs0Monitor
- Later →CVE-2026-68304Aug 10, 2026 · wifi: brcmfmac: fix 802.1X-SHA256 call trace warning0Monitor
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 | 3656a79f94c471827a08f2cacce5f94ad5e52c24 | Vendor (CNA) |
| Linux Linux | 37ff890f9c18dfbcf57e17199901d4fd1e4c174e | Vendor (CNA) |
| Linux Linux | 7746d588d42a4ac0117b68ed8e9b22a9da53dfb7 | Vendor (CNA) |
| Linux Linux | 7f48e3ddad8e97545b25788b8203b3a539df1621 | Vendor (CNA) |
| Linux Linux | 9005b221cb1f9c3c1a2ef656fb0e8fa80c0a187e | Vendor (CNA) |
| Linux Linux | ca0e8b661957f777591efe874cd9d9a63619cd99 | 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.
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 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-26-0800 · Aug 11, 2026(Linux Kernel Güvenlik Bildirimi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- 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
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- git.kernel.org/stable/c/37ff890f9c18dfbcf57e17199901d4fd1e4c174e
- git.kernel.org/stable/c/7746d588d42a4ac0117b68ed8e9b22a9da53dfb7
- git.kernel.org/stable/c/7f48e3ddad8e97545b25788b8203b3a539df1621
- git.kernel.org/stable/c/9005b221cb1f9c3c1a2ef656fb0e8fa80c0a187e
- git.kernel.org/stable/c/ca0e8b661957f777591efe874cd9d9a63619cd99
Vendor advisories and official records. Exploit/PoC links are deliberately left out.