Answer in brief
CVE-2025-21954 records a Critical severity (CVSS 9.8) vulnerability in netmem: prevent TX of unreadable skbs. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=65249feb6b3df9e17bab5911ee56fa7b0971e231 <454825019d2f0c59e5174ece9e713f45ad80beff || >=65249feb6b3df9e17bab5911ee56fa7b0971e231 <1c17c8ced25c5fbe424c7ad7ea11d33014a986b1 || >=65249feb6b3df9e17bab5911ee56fa7b0971e231 <f3600c867c99a2cc8038680ecf211089c50e7971 | 454825019d2f0c59e5174ece9e713f45ad80beff, 1c17c8ced25c5fbe424c7ad7ea11d33014a986b1, f3600c867c99a2cc8038680ecf211089c50e7971 |
| Linux/Linuxgeneric | 6.12 | Not reported |
Published upstream
Apr 1, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: netmem: prevent TX of unreadable skbs Currently on stable trees we have support for netmem/devmem RX but not TX. It is not safe to forward/redirect an RX unreadable netmem packet into the device's TX path, as the device may call dma-mapping APIs on dma addrs that should not be passed to it. Fix this by preventing the xmit of unreadable skbs. Tested by configuring tc redirect: sudo tc qdisc add dev eth1 ingress sudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \ tcp src_ip 192.168.1.12 action mirred egress redirect dev eth1 Before, I see unreadable skbs in the driver's TX path passed to dma mapping APIs. After, I don't see unreadable skbs in the driver's TX path passed to dma mapping APIs.
Quoted source text, attributed separately from HOL analysis.