usb: gadget: ncm: Avoid dropping datagrams of properly parsed NTBs
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: ncm: Avoid dropping datagrams of properly parsed NTBs It is observed sometimes when tethering is used over NCM with Windows 11 as host, at some instances, the gadget_giveback has one byte appended at the end of a proper NTB. When the NTB is parsed, unwrap call looks for any leftover bytes in SKB provided by u_ether and if there are any pending bytes, it treats them as a separate NTB and parses it. But in case the second NTB (as per unwrap call) is faulty/corrupt, all the datagrams that were parsed properly in the first NTB and saved in rx_list are dropped. Adding a few custom traces showed the following: [002] d..1 7828.532866: dwc3_gadget_giveback: ep1out: req 000000003868811a length 1025/16384 zsI ==> 0 [002] d..1 7828.532867: ncm_unwrap_ntb: K: ncm_unwrap_ntb toprocess: 1025 [002] d..1 7828.532867: ncm_unwrap_ntb: K: ncm_unwrap_ntb nth: 1751999342 [002] d..1 7828.532868: ncm_unwrap_ntb: K: ncm_unwrap_ntb seq: 0xce67 [002] d..1 7828.532868: ncm_unwrap_ntb: K: ncm_unwrap_ntb blk_len: 0x400 [002] d..1 7828.532868: ncm_unwrap_ntb: K: ncm_unwrap_ntb ndp_len: 0x10 [002] d..1 7828.532869: ncm_unwrap_ntb: K: Parsed NTB with 1 frames In this case, the giveback is of 1025 bytes and block length is 1024. The rest 1 byte (which is 0x00) won't be parsed resulting in drop of all datagrams in rx_list. Same is case with packets of size 2048: [002] d..1 7828.557948: dwc3_gadget_giveback: ep1out: req 0000000011dfd96e length 2049/16384 zsI ==> 0 [002] d..1 7828.557949: ncm_unwrap_ntb: K: ncm_unwrap_ntb nth: 1751999342 [002] d..1 7828.557950: ncm_unwrap_ntb: K: ncm_unwrap_ntb blk_len: 0x800 Lecroy shows one byte coming in extra confirming that the byte is coming in from PC: Transfer 2959 - Bytes Transferred(1025) Timestamp((18.524 843 590) - Transaction 8391 - Data(1025 bytes) Timestamp(18.524 843 590) --- Packet 4063861 Data(1024 bytes) Duration(2.117us) Idle(14.700ns) Timestamp(18.524 843 590) --- Packet 4063863 Data(1 byte) Duration(66.160ns) Time(282.000ns) Timestamp(18.524 845 722) According to Windows driver, no ZLP is needed if wBlockLength is non-zero, because the non-zero wBlockLength has already told the function side the size of transfer to be expected. However, there are in-market NCM devices that rely on ZLP as long as the wBlockLength is multiple of wMaxPacketSize. To deal with such devices, it pads an extra 0 at end so the transfer is no longer multiple of wMaxPacketSize.
- Published
- May 17, 2024
- Updated
- Jun 17, 2026
- EPSS
- 1.3% · 69th percentile
- CWE
- CWE-476
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Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux10.0
- linux linux kernel4.20 and later · before 5.4.270
- linux linux kernel5.5 and later · before 5.10.211
- linux linux kernel5.11 and later · before 5.15.150
- linux linux kernel2.6.38 and later · before 4.19.308
- linux linux kernel6.2 and later · before 6.6.19
- linux linux kernel6.7 and later · before 6.7.7
- linux linux kernel5.16 and later · before 6.1.80
- linux linux kernel6.8
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
- 2.6.38affected
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 059285e04ebb273d32323fbad5431c5b94f77e48affected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before a31cf46d108dabce3df80b3e5c07661e24912151affected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 57ca0e16f393bb21d69734e536e383a3a4c665fdaffected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 2cb66b62a5d64ccf09b0591ab86fb085fa491fc5affected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 35b604a37ec70d68b19dafd10bbacf1db505c9caaffected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 2b7ec68869d50ea998908af43b643bca7e54577eaffected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before c7f43900bc723203d7554d299a2ce844054fab8eaffected · git
- 9f6ce4240a2bf456402c15c06768059e5973f28c and later · before 76c51146820c5dac629f21deafab0a7039bc3ccdaffected · git
- before 2.6.38not 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 6.1.82-1 | 6.1.82-1 |
| Debian:13 | linux | before 6.7.7-1 | 6.7.7-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- 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
- CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV83Now
- CVE-2019-13272In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to creKEV77This week
- CVE-2013-6282The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the v6k and v7 ARM platforms do not validate certain addKEV77This week
- CVE-2013-2094The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, which allows loKEV77This week
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 | 059285e04ebb273d32323fbad5431c5b94f77e48 | Vendor (CNA) |
| Linux Linux | 2b7ec68869d50ea998908af43b643bca7e54577e | Vendor (CNA) |
| Linux Linux | 2cb66b62a5d64ccf09b0591ab86fb085fa491fc5 | Vendor (CNA) |
| Linux Linux | 35b604a37ec70d68b19dafd10bbacf1db505c9ca | Vendor (CNA) |
| Linux Linux | 57ca0e16f393bb21d69734e536e383a3a4c665fd | Vendor (CNA) |
| Linux Linux | 76c51146820c5dac629f21deafab0a7039bc3ccd | Vendor (CNA) |
| Linux Linux | a31cf46d108dabce3df80b3e5c07661e24912151 | Vendor (CNA) |
| Linux Linux | c7f43900bc723203d7554d299a2ce844054fab8e | Vendor (CNA) |
| debian:linux | 6.1.82-1 · 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.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
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
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- 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
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-476 · NULL Pointer DereferenceCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-secondary
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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- git.kernel.org/stable/c/059285e04ebb273d32323fbad5431c5b94f77e48
- git.kernel.org/stable/c/2b7ec68869d50ea998908af43b643bca7e54577e
- git.kernel.org/stable/c/2cb66b62a5d64ccf09b0591ab86fb085fa491fc5
- git.kernel.org/stable/c/35b604a37ec70d68b19dafd10bbacf1db505c9ca
- git.kernel.org/stable/c/57ca0e16f393bb21d69734e536e383a3a4c665fd
- git.kernel.org/stable/c/76c51146820c5dac629f21deafab0a7039bc3ccd
- git.kernel.org/stable/c/a31cf46d108dabce3df80b3e5c07661e24912151
- git.kernel.org/stable/c/c7f43900bc723203d7554d299a2ce844054fab8e
- lists.debian.org/debian-lts-announce/2024/06/msg00017.html
- lists.debian.org/debian-lts-announce/2024/06/msg00020.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.