CVE-2025-21910: wifi: cfg80211: regulatory: improve invalid hints checking
Noroxi assessment
Priority: Monitor (action score 22/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.23% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 17aa34c84867f6cd181a5743e1c647e7766962a6, 35ef07112b61b06eb30683a6563c9f6378c02476, 59b348be7597c4a9903cb003c69e37df20c04a30.
Low priority for now. Upgrade to Linux Linux 17aa34c84867f6cd181a5743e1c647e7766962a6, 35ef07112b61b06eb30683a6563c9f6378c02476, 59b348be7597c4a9903cb003c69e37df20c04a30 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: regulatory: improve invalid hints checking Syzbot keeps reporting an issue [1] that occurs when erroneous symbols sent from userspace get through into user_alpha2[] via regulatory_hint_user() call. Such invalid regulatory hints should be rejected. While a sanity check from commit 47caf685a685 ("cfg80211: regulatory: reject invalid hints") looks to be enough to deter these very cases, there is a way to get around it due to 2 reasons. 1) The way isalpha() works, symbols other than latin lower and upper letters may be used to determine a country/domain. For instance, greek letters will also be considered upper/lower letters and for such characters isalpha() will return true as well. However, ISO-3166-1 alpha2 codes should only hold latin characters. 2) While processing a user regulatory request, between reg_process_hint_user() and regulatory_hint_user() there happens to be a call to queue_regulatory_request() which modifies letters in request->alpha2[] with toupper(). This works fine for latin symbols, less so for weird letter characters from the second part of _ctype[]. Syzbot triggers a warning in is_user_regdom_saved() by first sending over an unexpected non-latin letter that gets malformed by toupper() into a character that ends up failing isalpha() check. Prevent this by enhancing is_an_alpha2() to ensure that incoming symbols are latin letters and nothing else. [1] Syzbot report: ------------[ cut here ]------------ Unexpected user alpha2: A� WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 is_user_regdom_saved net/wireless/reg.c:440 [inline] WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_alpha2 net/wireless/reg.c:3424 [inline] WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516 Modules linked in: CPU: 1 UID: 0 PID: 964 Comm: kworker/1:2 Not tainted 6.12.0-rc5-syzkaller-00044-gc1e939a21eb1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient crda_timeout_work RIP: 0010:is_user_regdom_saved net/wireless/reg.c:440 [inline] RIP: 0010:restore_alpha2 net/wireless/reg.c:3424 [inline] RIP: 0010:restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516 ... Call Trace: <TASK> crda_timeout_work+0x27/0x50 net/wireless/reg.c:542 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK>
- Published
- Apr 1, 2025
- Updated
- Nov 5, 2026
- EPSS
- 0.2% · 14th percentile
- CWE
- —
Report tools
Action score
22
Monitor
Low priority for now.
- CVSS
- 22 / 40 · 5.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel2.6.34 and later · before 5.4.291
- linux linux kernel5.5 and later · before 5.10.235
- linux linux kernel5.11 and later · before 5.15.179
- linux linux kernel5.16 and later · before 6.1.131
- linux linux kernel6.2 and later · before 6.6.83
- linux linux kernel6.7 and later · before 6.12.19
- linux linux kernel6.13 and later · before 6.13.7
- linux linux kernel6.14
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 2.6.34affected
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before 62b1a9bbfebba4b4c2bb6c1ede9ef7ecee7a9ff6affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before da3f599517ef2ea851208df3229d07728d238dc5affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before 6a5e3b23054cee3b92683d1467e3fa83921f5622affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before f4112cb477c727a65787a4065a75ca593bb5b2f4affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before 35ef07112b61b06eb30683a6563c9f6378c02476affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before be7c5f00aa7f1344293e4d48d0e12be83a2f223daffected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before 17aa34c84867f6cd181a5743e1c647e7766962a6affected · git
- 09d989d179d0c679043556dda77c51b41a2dae7e and later · before 59b348be7597c4a9903cb003c69e37df20c04a30affected · git
- before 2.6.34not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.133-1 | 6.1.133-1 |
| Debian:13 | linux | before 6.12.19-1 | 6.12.19-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2025-21907Apr 1, 2025 · mm: memory-failure: update ttu flag inside unmap_poisoned_folio22Monitor
- ← EarlierCVE-2025-21909Apr 1, 2025 · wifi: nl80211: reject cooked mode if it is set along with other flags22Monitor
- Later →CVE-2025-21913Apr 1, 2025 · x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range()22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 17aa34c84867f6cd181a5743e1c647e7766962a6 | Vendor (CNA) |
| Linux Linux | 35ef07112b61b06eb30683a6563c9f6378c02476 | Vendor (CNA) |
| Linux Linux | 59b348be7597c4a9903cb003c69e37df20c04a30 | Vendor (CNA) |
| Linux Linux | 62b1a9bbfebba4b4c2bb6c1ede9ef7ecee7a9ff6 | Vendor (CNA) |
| Linux Linux | 6a5e3b23054cee3b92683d1467e3fa83921f5622 | Vendor (CNA) |
| Linux Linux | be7c5f00aa7f1344293e4d48d0e12be83a2f223d | Vendor (CNA) |
| Linux Linux | da3f599517ef2ea851208df3229d07728d238dc5 | Vendor (CNA) |
| Linux Linux | f4112cb477c727a65787a4065a75ca593bb5b2f4 | Vendor (CNA) |
| debian:linux | 6.1.133-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (9 more)Show less
- git.kernel.org/stable/c/35ef07112b61b06eb30683a6563c9f6378c02476
- git.kernel.org/stable/c/59b348be7597c4a9903cb003c69e37df20c04a30
- git.kernel.org/stable/c/62b1a9bbfebba4b4c2bb6c1ede9ef7ecee7a9ff6
- git.kernel.org/stable/c/6a5e3b23054cee3b92683d1467e3fa83921f5622
- git.kernel.org/stable/c/be7c5f00aa7f1344293e4d48d0e12be83a2f223d
- git.kernel.org/stable/c/da3f599517ef2ea851208df3229d07728d238dc5
- git.kernel.org/stable/c/f4112cb477c727a65787a4065a75ca593bb5b2f4
- lists.debian.org/debian-lts-announce/2025/05/msg00030.html
- lists.debian.org/debian-lts-announce/2025/05/msg00045.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.