Persistent memory leak via stale truesize subtraction
Published Jan 23, 2026 · Updated Jan 23, 2026
Memory-accounting error in the Linux kernel allows local users to cause a persistent memory leak during GRO packet forwarding. skb_segment_list unconditionally adds each orphaned fragment's truesize to delta_truesize and subtracts it from the head SKB, although the fragments no longer carry socket charges. The path requires SKB_GSO_FRAGLIST packets constructed by GRO; the under-count keeps sk_wmem_alloc nonzero and prevents affected sockets from being destroyed.
Summary
What happened
Memory-accounting error in the Linux kernel allows local users to cause a persistent memory leak during GRO packet forwarding. skb_segment_list unconditionally adds each orphaned fragment's truesize to delta_truesize and subtracts it from the head SKB, although the fragments no longer carry socket charges. The path requires SKB_GSO_FRAGLIST packets constructed by GRO; the under-count keeps sk_wmem_alloc nonzero and prevents affected sockets from being destroyed.
The record
- CVE
- CVE-2026-22979
- Published
- Jan 23, 2026
- Updated
- Jan 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-401, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 23, 2026CVE publishedPublication date reported by the CVE source.
- Jan 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2eeab8c47c3c0276e0746bc382f405c9a236a5ad <0b27828ebd1ed3107d7929c3737adbe862e99e74
- Affected versionversion=5b3b67f731296027cceb3efad881ae281213f86f
- Affected versionversion=6.9
- Affected versionversion=d225b0ac96dc40d7e8ae2bc227eb2c56e130975f
- Affected versionversion=ed4cccef64c1d0d5b91e69f7a8a6697c3a865486 <238e03d0466239410b72294b79494e43d4fabe77
- Affected versionversion=ed4cccef64c1d0d5b91e69f7a8a6697c3a865486 <3264881431e308b9c72cb8a0159d57a56d67dd79
- Affected versionversion=ed4cccef64c1d0d5b91e69f7a8a6697c3a865486 <c114a32a2e70b82d447f409f7ffcfa3058f9d5bd
- Affected versionversion=fc126c1d51e9552eacd2d717b9ffe9262a8a4cd6 <88bea149db2057112af3aaf63534b24fab5858ab
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo