Answer in brief
CVE-2025-21872 records a Medium severity (CVSS 5.5) vulnerability in efi: Don't map the entire mokvar table to determine its size. 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 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). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <46c0454ffb78ce9d3355a3cccac86383ea8ddd55 || >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <f17a72ac7dd6f9469c9e6185bdbb22dbb744dd74 || >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <ea3f0b362dfe4ef885ef812bfaf4088176422c91 || >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <65f4aebb8127708ba668dd938e83b8558abfc5cd || >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <97bd560b6cc4c26386a53b4881bf03e96f9ba03a || >=58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 <2b90e7ace79774a3540ce569e000388f8d22c9e0 | 46c0454ffb78ce9d3355a3cccac86383ea8ddd55, f17a72ac7dd6f9469c9e6185bdbb22dbb744dd74, ea3f0b362dfe4ef885ef812bfaf4088176422c91, 65f4aebb8127708ba668dd938e83b8558abfc5cd, 97bd560b6cc4c26386a53b4881bf03e96f9ba03a, 2b90e7ace79774a3540ce569e000388f8d22c9e0 |
| Linux/Linuxgeneric | 5.10 | Not reported |
Published upstream
Mar 27, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 30, 2026
In the Linux kernel, the following vulnerability has been resolved: efi: Don't map the entire mokvar table to determine its size Currently, when validating the mokvar table, we (re)map the entire table on each iteration of the loop, adding space as we discover new entries. If the table grows over a certain size, this fails due to limitations of early_memmap(), and we get a failure and traceback: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:139 __early_ioremap+0xef/0x220 ... Call Trace: <TASK> ? __early_ioremap+0xef/0x220 ? __warn.cold+0x93/0xfa ? __early_ioremap+0xef/0x220 ? report_bug+0xff/0x140 ? early_fixup_exception+0x5d/0xb0 ? early_idt_handler_common+0x2f/0x3a ? __early_ioremap+0xef/0x220 ? efi_mokvar_table_init+0xce/0x1d0 ? setup_arch+0x864/0xc10 ? start_kernel+0x6b/0xa10 ? x86_64_start_reservations+0x24/0x30 ? x86_64_start_kernel+0xed/0xf0 ? common_startup_64+0x13e/0x141 </TASK> ---[ end trace 0000000000000000 ]--- mokvar: Failed to map EFI MOKvar config table pa=0x7c4c3000, size=265187. Mapping the entire structure isn't actually necessary, as we don't ever need more than one entry header mapped at once. Changes efi_mokvar_table_init() to only map each entry header, not the entire table, when determining the table size. Since we're not mapping any data past the variable name, it also changes the code to enforce that each variable name is NUL terminated, rather than attempting to verify it in place.
Quoted source text, attributed separately from HOL analysis.