Answer in brief
CVE-2025-39848 records a Unknown severity vulnerability in ax25: properly unshare skbs in ax25_kiss_rcv(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC CN 4100 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. 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), Siemens/SIMATIC CN 4100 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <42b46684e2c78ee052d8c2ee8d9c2089233c9094 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5b079be1b9da49ad88fc304c874d4be7085f7883 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2bd0f67212908243ce88e35bf69fa77155b47b14 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <01a2984cb803f2d487b7074f9718db2bf3531f69 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7d449b7a6c8ee434d10a483feed7c5c50108cf56 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <89064cf534bea4bb28c83fe6bbb26657b19dd5fe || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b1c71d674a308d2fbc83efcf88bfc4217a86aa17 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8156210d36a43e76372312c87eb5ea3dbb405a85 | 42b46684e2c78ee052d8c2ee8d9c2089233c9094, 5b079be1b9da49ad88fc304c874d4be7085f7883, 2bd0f67212908243ce88e35bf69fa77155b47b14, 01a2984cb803f2d487b7074f9718db2bf3531f69, 7d449b7a6c8ee434d10a483feed7c5c50108cf56, 89064cf534bea4bb28c83fe6bbb26657b19dd5fe, b1c71d674a308d2fbc83efcf88bfc4217a86aa17, 8156210d36a43e76372312c87eb5ea3dbb405a85 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
| Siemens/SIMATIC CN 4100generic | >=0 <V5.0 | V5.0 |
Published upstream
Sep 19, 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: ax25: properly unshare skbs in ax25_kiss_rcv() Bernard Pidoux reported a regression apparently caused by commit c353e8983e0d ("net: introduce per netns packet chains"). skb->dev becomes NULL and we crash in __netif_receive_skb_core(). Before above commit, different kind of bugs or corruptions could happen without a major crash. But the root cause is that ax25_kiss_rcv() can queue/mangle input skb without checking if this skb is shared or not. Many thanks to Bernard Pidoux for his help, diagnosis and tests. We had a similar issue years ago fixed with commit 7aaed57c5c28 ("phonet: properly unshare skbs in phonet_rcv()").
Quoted source text, attributed separately from HOL analysis.