Answer in brief
CVE-2025-21846 records a Medium severity (CVSS 5.5) vulnerability in acct: perform last write from workqueue. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2025-21846 records a Medium severity (CVSS 5.5) vulnerability in acct: perform last write from workqueue. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic) and additional mapped packages. 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 5.5. 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 S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b03782ae707cc45e65242c7cddd8e28f1c22cde5 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5d5b936cfa4b0d5670ca7420ef165a074bc008eb || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5ee8da9bea70dda492d61f075658939af33d8410 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5c928e14a2ccd99462f2351ead627b58075bb736 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5a59ced8ffc71973d42c82484a719c8f6ac8f7f7 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a8136afca090412a36429cb6c2543c714d9c0f84 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <56d5f3eba3f5de0efdd556de4ef381e109b973a9 | 8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e, b03782ae707cc45e65242c7cddd8e28f1c22cde5, 5d5b936cfa4b0d5670ca7420ef165a074bc008eb, 5ee8da9bea70dda492d61f075658939af33d8410, 5c928e14a2ccd99462f2351ead627b58075bb736, 5a59ced8ffc71973d42c82484a719c8f6ac8f7f7, a8136afca090412a36429cb6c2543c714d9c0f84, 56d5f3eba3f5de0efdd556de4ef381e109b973a9 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystemgeneric | >=0 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
Published upstream
Mar 12, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 14, 2026
In the Linux kernel, the following vulnerability has been resolved: acct: perform last write from workqueue In [1] it was reported that the acct(2) system call can be used to trigger NULL deref in cases where it is set to write to a file that triggers an internal lookup. This can e.g., happen when pointing acc(2) to /sys/power/resume. At the point the where the write to this file happens the calling task has already exited and called exit_fs(). A lookup will thus trigger a NULL-deref when accessing current->fs. Reorganize the code so that the the final write happens from the workqueue but with the caller's credentials. This preserves the (strange) permission model and has almost no regression risk. This api should stop to exist though.
Quoted source text, attributed separately from HOL analysis.
CVSS is 5.5. 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 S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b03782ae707cc45e65242c7cddd8e28f1c22cde5 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5d5b936cfa4b0d5670ca7420ef165a074bc008eb || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5ee8da9bea70dda492d61f075658939af33d8410 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5c928e14a2ccd99462f2351ead627b58075bb736 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5a59ced8ffc71973d42c82484a719c8f6ac8f7f7 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a8136afca090412a36429cb6c2543c714d9c0f84 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <56d5f3eba3f5de0efdd556de4ef381e109b973a9 | 8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e, b03782ae707cc45e65242c7cddd8e28f1c22cde5, 5d5b936cfa4b0d5670ca7420ef165a074bc008eb, 5ee8da9bea70dda492d61f075658939af33d8410, 5c928e14a2ccd99462f2351ead627b58075bb736, 5a59ced8ffc71973d42c82484a719c8f6ac8f7f7, a8136afca090412a36429cb6c2543c714d9c0f84, 56d5f3eba3f5de0efdd556de4ef381e109b973a9 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystemgeneric | >=0 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
Published upstream
Mar 12, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 14, 2026
In the Linux kernel, the following vulnerability has been resolved: acct: perform last write from workqueue In [1] it was reported that the acct(2) system call can be used to trigger NULL deref in cases where it is set to write to a file that triggers an internal lookup. This can e.g., happen when pointing acc(2) to /sys/power/resume. At the point the where the write to this file happens the calling task has already exited and called exit_fs(). A lookup will thus trigger a NULL-deref when accessing current->fs. Reorganize the code so that the the final write happens from the workqueue but with the caller's credentials. This preserves the (strange) permission model and has almost no regression risk. This api should stop to exist though.
Quoted source text, attributed separately from HOL analysis.