Answer in brief
CVE-2025-21972 records a Unknown severity vulnerability in net: mctp: unshare packets when reassembling. 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.
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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=4a992bbd365094730a31bae1e12a6ca695336d57 <5c47d5bfa7b096cf8890afac32141c578583f8e0 || >=4a992bbd365094730a31bae1e12a6ca695336d57 <f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e || >=4a992bbd365094730a31bae1e12a6ca695336d57 <f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc | 5c47d5bfa7b096cf8890afac32141c578583f8e0, f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e, f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc |
| Linux/Linuxgeneric | 5.15 | 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: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly isn't shared with other packets. This avoids incorrect reassembly when packets are cloned, and prevents a memory leak due to circular references between fragments and their skb_shared_info. The upcoming MCTP-over-USB driver uses skb_clone which can trigger the problem - other MCTP drivers don't share SKBs. A kunit test is added to reproduce the issue.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2025-21972 records a Unknown severity vulnerability in net: mctp: unshare packets when reassembling. 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.
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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=4a992bbd365094730a31bae1e12a6ca695336d57 <5c47d5bfa7b096cf8890afac32141c578583f8e0 || >=4a992bbd365094730a31bae1e12a6ca695336d57 <f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e || >=4a992bbd365094730a31bae1e12a6ca695336d57 <f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc | 5c47d5bfa7b096cf8890afac32141c578583f8e0, f44fff3d3c6cd67b6f348b821d73c4d6888c7a6e, f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc |
| Linux/Linuxgeneric | 5.15 | 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: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly isn't shared with other packets. This avoids incorrect reassembly when packets are cloned, and prevents a memory leak due to circular references between fragments and their skb_shared_info. The upcoming MCTP-over-USB driver uses skb_clone which can trigger the problem - other MCTP drivers don't share SKBs. A kunit test is added to reproduce the issue.
Quoted source text, attributed separately from HOL analysis.