CVE-2024-49947: net: test for not too small csum_start in virtio_net_hdr_to_skb()
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 49d14b54a527289d09a9480f214b8c586322310a, 4cc0648e9e3240496835dc698ace1d046d8d57ea, 6.6.55.
Low priority for now. Upgrade to Linux Linux 49d14b54a527289d09a9480f214b8c586322310a, 4cc0648e9e3240496835dc698ace1d046d8d57ea, 6.6.55 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: net: test for not too small csum_start in virtio_net_hdr_to_skb() syzbot was able to trigger this warning [1], after injecting a malicious packet through af_packet, setting skb->csum_start and thus the transport header to an incorrect value. We can at least make sure the transport header is after the end of the network header (with a estimated minimal size). [1] [ 67.873027] skb len=4096 headroom=16 headlen=14 tailroom=0 mac=(-1,-1) mac_len=0 net=(16,-6) trans=10 shinfo(txflags=0 nr_frags=1 gso(size=0 type=0 segs=0)) csum(0xa start=10 offset=0 ip_summed=3 complete_sw=0 valid=0 level=0) hash(0x0 sw=0 l4=0) proto=0x0800 pkttype=0 iif=0 priority=0x0 mark=0x0 alloc_cpu=10 vlan_all=0x0 encapsulation=0 inner(proto=0x0000, mac=0, net=0, trans=0) [ 67.877172] dev name=veth0_vlan feat=0x000061164fdd09e9 [ 67.877764] sk family=17 type=3 proto=0 [ 67.878279] skb linear: 00000000: 00 00 10 00 00 00 00 00 0f 00 00 00 08 00 [ 67.879128] skb frag: 00000000: 0e 00 07 00 00 00 28 00 08 80 1c 00 04 00 00 02 [ 67.879877] skb frag: 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.880647] skb frag: 00000020: 00 00 02 00 00 00 08 00 1b 00 00 00 00 00 00 00 [ 67.881156] skb frag: 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.881753] skb frag: 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.882173] skb frag: 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.882790] skb frag: 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.883171] skb frag: 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.883733] skb frag: 00000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.884206] skb frag: 00000090: 00 00 00 00 00 00 00 00 00 00 69 70 76 6c 61 6e [ 67.884704] skb frag: 000000a0: 31 00 00 00 00 00 00 00 00 00 2b 00 00 00 00 00 [ 67.885139] skb frag: 000000b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.885677] skb frag: 000000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.886042] skb frag: 000000d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.886408] skb frag: 000000e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.887020] skb frag: 000000f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 67.887384] skb frag: 00000100: 00 00 [ 67.887878] ------------[ cut here ]------------ [ 67.887908] offset (-6) >= skb_headlen() (14) [ 67.888445] WARNING: CPU: 10 PID: 2088 at net/core/dev.c:3332 skb_checksum_help (net/core/dev.c:3332 (discriminator 2)) [ 67.889353] Modules linked in: macsec macvtap macvlan hsr wireguard curve25519_x86_64 libcurve25519_generic libchacha20poly1305 chacha_x86_64 libchacha poly1305_x86_64 dummy bridge sr_mod cdrom evdev pcspkr i2c_piix4 9pnet_virtio 9p 9pnet netfs [ 67.890111] CPU: 10 UID: 0 PID: 2088 Comm: b363492833 Not tainted 6.11.0-virtme #1011 [ 67.890183] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 67.890309] RIP: 0010:skb_checksum_help (net/core/dev.c:3332 (discriminator 2)) [ 67.891043] Call Trace: [ 67.891173] <TASK> [ 67.891274] ? __warn (kernel/panic.c:741) [ 67.891320] ? skb_checksum_help (net/core/dev.c:3332 (discriminator 2)) [ 67.891333] ? report_bug (lib/bug.c:180 lib/bug.c:219) [ 67.891348] ? handle_bug (arch/x86/kernel/traps.c:239) [ 67.891363] ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1)) [ 67.891372] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621) [ 67.891388] ? skb_checksum_help (net/core/dev.c:3332 (discriminator 2)) [ 67.891399] ? skb_checksum_help (net/core/dev.c:3332 (discriminator 2)) [ 67.891416] ip_do_fragment (net/ipv4/ip_output.c:777 (discriminator 1)) [ 67.891448] ? __ip_local_out (./include/linux/skbuff.h:1146 ./include/net/l3mdev.h:196 ./include/net/l3mdev.h:213 ne ---truncated---
- Published
- Oct 21, 2024
- Updated
- Jun 17, 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 kernel6.6.14 and later · before 6.6.55
- linux linux kernel6.8 and later · before 6.10.14
- linux linux kernel6.11 and later · before 6.11.3
- linux linux kernel6.12
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
- 765290b628c2fb764bdfaf8088754439665751e8, 6.8affected
- 342c88f406c2acd3dd00767aeacafe883cebb374 and later · before d9dfd41e32ccc5198033ddd1ff1516822dfefa5aaffected · git
- 9181d6f8a2bb32d158de66a84164fac05e3ddd18 and later · before 4cc0648e9e3240496835dc698ace1d046d8d57eaaffected · git
- 9181d6f8a2bb32d158de66a84164fac05e3ddd18 and later · before 7711c419a915ee0dd91c125d2b967bbf2a72e9acaffected · git
- 9181d6f8a2bb32d158de66a84164fac05e3ddd18 and later · before 49d14b54a527289d09a9480f214b8c586322310aaffected · git
- 6.6.14 and later · before 6.6.55affected · semver
- 6.7.2 and later · before 6.8affected · semver
- before 6.8not affected · semver
- 6.6.55 and later · up to and including 6.6.*not affected · semver
- 6.10.14 and later · up to and including 6.10.*not 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:13 | linux | before 6.11.4-1 | 6.11.4-1 |
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-2024-49943Oct 21, 2024 · drm/xe/guc_submit: add missing locking in wedged_fini22Monitor
- ← EarlierCVE-2024-49946Oct 21, 2024 · ppp: do not assume bh is held in ppp_channel_bridge_input()22Monitor
- Later →CVE-2024-49950Oct 21, 2024 · Bluetooth: L2CAP: Fix uaf in l2cap_connect31Monitor
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 | 49d14b54a527289d09a9480f214b8c586322310a | Vendor (CNA) |
| Linux Linux | 4cc0648e9e3240496835dc698ace1d046d8d57ea | Vendor (CNA) |
| Linux Linux | 6.6.55 | Vendor (CNA) |
| Linux Linux | 6.8 | Vendor (CNA) |
| Linux Linux | 7711c419a915ee0dd91c125d2b967bbf2a72e9ac | Vendor (CNA) |
| Linux Linux | d9dfd41e32ccc5198033ddd1ff1516822dfefa5a | Vendor (CNA) |
| debian:linux | 6.11.4-1 · Debian:13 | 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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (3 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.