Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2024-49855: nbd: fix race between timeout and normal completion

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 0.46% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: Linux Linux 5.18, 5.19, 5236ada8ebbd9e7461f17477357582f5be4f46f7; azl3 kernel 6.6.51.1-5 on Azure Linux 3.0 6.6.56.1-5; azl3 kernel 6.6.56.1-5 on Azure Linux 3.0 6.6.56.1-5.
  • Severity is disputed: the assigning authority (CNA) scores it 9.8, NVD 7.0.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 5.18, 5.19, 5236ada8ebbd9e7461f17477357582f5be4f46f7; azl3 kernel 6.6.51.1-5 on Azure Linux 3.0 6.6.56.1-5; azl3 kernel 6.6.56.1-5 on Azure Linux 3.0 6.6.56.1-5 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: nbd: fix race between timeout and normal completion If request timetout is handled by nbd_requeue_cmd(), normal completion has to be stopped for avoiding to complete this requeued request, other use-after-free can be triggered. Fix the race by clearing NBD_CMD_INFLIGHT in nbd_requeue_cmd(), meantime make sure that cmd->lock is grabbed for clearing the flag and the requeue.

HighCVSS 7.0 · v3.1—No exploit Fix available
Published
Oct 21, 2024
Updated
Aug 5, 2026
EPSS
0.4% · 40th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.0
CNA · Linux
9.8
2.8 point gap

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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.

Follow CVE-2024-49855

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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 help

Affected 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.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel5.18.4 and later · before 5.19
  • linux linux kernel5.19 and later · before 6.1.113
  • linux linux kernel6.2 and later · before 6.6.54
  • linux linux kernel6.7 and later · before 6.10.13
  • linux linux kernel6.11 and later · before 6.11.2
  • linux linux kernel5.17.15

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

    • cdf62c535a9bfd5ff0eef4b91669da39d8abc0c3, 5171ef20bae852ff38f4cfdb368bcdcc744776d0, 5.19affected
    • 2895f1831e911ca87d4efdf43e35eb72a0c7e66e and later · before 9c25faf72d780a9c71081710cd48759d61ff6e9baffected · git
    • 2895f1831e911ca87d4efdf43e35eb72a0c7e66e and later · before 6e73b946a379a1dfbb62626af93843bdfb53753daffected · git
    • 2895f1831e911ca87d4efdf43e35eb72a0c7e66e and later · before 5236ada8ebbd9e7461f17477357582f5be4f46f7affected · git
    • 2895f1831e911ca87d4efdf43e35eb72a0c7e66e and later · before 9a74c3e6c0d686c26ba2aab66d15ddb89dc139ccaffected · git
    • 2895f1831e911ca87d4efdf43e35eb72a0c7e66e and later · before c9ea57c91f03bcad415e1a20113bdb2077bcf990affected · git
    • 5.17.15 and later · before 5.18affected · semver
    • 5.18.4 and later · before 5.19affected · semver
    • before 5.19not affected · semver
    • 6.1.113 and later · up to and including 6.1.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.115-16.1.115-1
Debian:13linuxbefore 6.11.2-16.11.2-1
SUSE:Linux Enterprise Live Patching 15 SP5kernel-livepatch-SLE15-SP5_Update_15before 16-150500.2.216-150500.2.2
SUSE:Linux Enterprise Live Patching 15 SP5kernel-livepatch-SLE15-SP5_Update_19before 9-150500.2.29-150500.2.2
SUSE:Linux Enterprise Live Patching 15 SP6kernel-livepatch-SLE15-SP6_Update_2before 15-150600.2.215-150600.2.2
SUSE:Linux Enterprise Live Patching 15 SP6kernel-livepatch-SLE15-SP6_Update_4before 11-150600.2.211-150600.2.2
SUSE:Linux Enterprise Live Patching 15 SP6kernel-livepatch-SLE15-SP6-RT_Update_0before 16-150600.3.116-150600.3.1
SUSE:Linux Enterprise Live Patching 15 SP6kernel-livepatch-SLE15-SP6-RT_Update_4before 10-150600.2.110-150600.2.1
SUSE:Linux Micro 6.0kernel-livepatch-MICRO-6-0_Update_2before 6-1.16-1.1
SUSE:Linux Micro 6.0kernel-livepatch-MICRO-6-0_Update_3before 6-1.26-1.2
SUSE:Linux Micro 6.0kernel-livepatch-MICRO-6-0-RT_Update_2before 6-1.16-1.1
SUSE:Linux Micro 6.0kernel-livepatch-MICRO-6-0-RT_Update_3before 6-1.26-1.2

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • 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 KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2024-49853Oct 21, 2024 · firmware: arm_scmi: Fix double free in OPTEE transport
    31Monitor
  • ← EarlierCVE-2024-49854Oct 21, 2024 · block, bfq: fix uaf for accessing waker_bfqq after splitting
    31Monitor
  • Later →CVE-2024-49856Oct 21, 2024 · x86/sgx: Fix deadlock in SGX NUMA node search
    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 / packageFixed versionSource
Linux Linux5.18Vendor (CNA)
Linux Linux5.19Vendor (CNA)
Linux Linux5236ada8ebbd9e7461f17477357582f5be4f46f7Vendor (CNA)
Linux Linux6e73b946a379a1dfbb62626af93843bdfb53753dVendor (CNA)
Linux Linux9a74c3e6c0d686c26ba2aab66d15ddb89dc139ccVendor (CNA)
Linux Linux9c25faf72d780a9c71081710cd48759d61ff6e9bVendor (CNA)
Linux Linuxc9ea57c91f03bcad415e1a20113bdb2077bcf990Vendor (CNA)
azl3 kernel 6.6.51.1-5 on Azure Linux 3.06.6.56.1-5 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 kernel 6.6.56.1-5 on Azure Linux 3.06.6.56.1-5 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.115-1 · Debian:12Package registry (OSV)
suse:kernel-livepatch-MICRO-6-0_Update_26-1.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-livepatch-MICRO-6-0_Update_36-1.2 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-livepatch-MICRO-6-0-RT_Update_26-1.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-livepatch-MICRO-6-0-RT_Update_36-1.2 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-livepatch-SLE15-SP5_Update_1516-150500.2.2 · SUSE:Linux Enterprise Live Patching 15 SP5Package registry (OSV)
suse:kernel-livepatch-SLE15-SP5_Update_199-150500.2.2 · SUSE:Linux Enterprise Live Patching 15 SP5Package registry (OSV)
suse:kernel-livepatch-SLE15-SP6_Update_215-150600.2.2 · SUSE:Linux Enterprise Live Patching 15 SP6Package registry (OSV)
suse:kernel-livepatch-SLE15-SP6_Update_411-150600.2.2 · SUSE:Linux Enterprise Live Patching 15 SP6Package registry (OSV)
suse:kernel-livepatch-SLE15-SP6-RT_Update_016-150600.3.1 · SUSE:Linux Enterprise Live Patching 15 SP6Package registry (OSV)
suse:kernel-livepatch-SLE15-SP6-RT_Update_410-150600.2.1 · SUSE:Linux Enterprise Live Patching 15 SP6Package 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 researchers

Finders, 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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

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.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

c
free(dev->buf);/* ... another thread is still running ... */process(dev->buf);

Fixed

c
lock(&dev->lock);free(dev->buf);dev->buf = NULL;unlock(&dev->lock);

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

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records