CVE-2026-52955: libceph: Fix potential out-of-bounds access in crush_decode()
Noroxi assessment
Priority: Monitor (action score 39/100)
- 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: 0.38% (FIRST EPSS).
- 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.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: Linux Linux 0f3604cbe4df14c5e58288ac9f57511e726a222d, 3f42508191e129ee6b5ea96578d5cab14f2a013a, 4c79fc2d598694bda845b46229c9d48b65042970.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 0f3604cbe4df14c5e58288ac9f57511e726a222d, 3f42508191e129ee6b5ea96578d5cab14f2a013a, 4c79fc2d598694bda845b46229c9d48b65042970 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: libceph: Fix potential out-of-bounds access in crush_decode() A message of type CEPH_MSG_OSD_MAP containing a crush map with at least one bucket has two fields holding the bucket algorithm. If the values in these two fields differ, an out-of-bounds access can occur. This is the case because the first algorithm field (alg) is used to allocate the correct amount of memory for a bucket of this type, while the second algorithm field inside the bucket (b->alg) is used in the subsequent processing. This patch fixes the issue by adding a check that compares alg and b->alg and aborts the processing in case they differ. Furthermore, b->alg is set to 0 in this case, because the destruction of the crush map also uses this field to determine the bucket type, which can again result in an out-of-bounds access when trying to free the memory pointed to by the fields of the bucket. To correctly free the memory allocated for the bucket in such a case, the corresponding call to kfree is moved from the algorithm-specific crush_destroy_bucket functions to the generic crush_destroy_bucket().
- Published
- Jun 24, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.3% · 32th percentile
- CWE
- CWE-125
Report tools
Action score
39
Low priority for now.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 9.8
- NVD has not scored this yet; the score shown is the CNA’s.
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.
Is your version affected? Check itNoroxi 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 kernel2.6.34.1 and later · before 5.10.258
- linux linux kernel5.11 and later · before 5.15.209
- linux linux kernel5.16 and later · before 6.1.175
- linux linux kernel6.2 and later · before 6.6.141
- linux linux kernel6.7 and later · before 6.12.91
- linux linux kernel6.13 and later · before 6.18.33
- linux linux kernel6.19 and later · before 7.0.10
- linux linux kernel2.6.34
- linux linux kernel7.1
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
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before 6e70ef53e818c53eab28d7b0026b7fd03dddaba5affected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before ebe76d58a48a48031b98543d86c4cd30a825b622affected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before 3f42508191e129ee6b5ea96578d5cab14f2a013aaffected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before ea0d42137f0c06da71e37ffc647aab4c5309599aaffected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before cceb10023e76bc89f3fe9238ebd0ccab0fc7c7c5affected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before 0f3604cbe4df14c5e58288ac9f57511e726a222daffected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before fb176a99e4c1a5a8448a83d83d3606203ba81faaaffected · git
- f24e9980eb860d8600cbe5ef3d2fd9295320d229 and later · before 4c79fc2d598694bda845b46229c9d48b65042970affected · 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 6.1.176-1 | 6.1.176-1 |
| Debian:13 | linux | before 6.12.94-1 | 6.12.94-1 |
| Debian:14 | linux | before 7.0.10-1 | 7.0.10-1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-64kb | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-docs | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-obs-build | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-syms | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-64kb | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-docs | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-obs-build | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-syms | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise Live Patching 15 SP4 | kernel-livepatch-SLE15-SP4_Update_57 | before 1-150400.9.3.1 | 1-150400.9.3.1 |
| SUSE:Linux Enterprise Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_43 | before 1-150500.11.5.1 | 1-150500.11.5.1 |
| SUSE:Linux Enterprise Micro 5.3 | kernel-default | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise Micro 5.3 | kernel-default-base | before 5.14.21-150400.24.228.1.150400.24.116.1 | 5.14.21-150400.24.228.1.150400.24.116.1 |
| SUSE:Linux Enterprise Micro 5.3 | kernel-rt | before 5.14.21-150400.15.176.1 | 5.14.21-150400.15.176.1 |
| SUSE:Linux Enterprise Micro 5.3 | kernel-source | before 5.14.21-150400.24.228.1 | 5.14.21-150400.24.228.1 |
| SUSE:Linux Enterprise Micro 5.3 | kernel-source-rt | before 5.14.21-150400.15.176.1 | 5.14.21-150400.15.176.1 |
| SUSE:Linux Enterprise Micro 5.5 | kernel-default | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise Micro 5.5 | kernel-default-base | before 5.14.21-150500.55.177.1.150500.6.83.2 | 5.14.21-150500.55.177.1.150500.6.83.2 |
| SUSE:Linux Enterprise Micro 5.5 | kernel-rt | before 5.14.21-150500.13.151.1 | 5.14.21-150500.13.151.1 |
| SUSE:Linux Enterprise Micro 5.5 | kernel-source | before 5.14.21-150500.55.177.1 | 5.14.21-150500.55.177.1 |
| SUSE:Linux Enterprise Micro 5.5 | kernel-source-rt | before 5.14.21-150500.13.151.1 | 5.14.21-150500.13.151.1 |
| SUSE:Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | kernel-default | before 3.0.101-108.220.1 | 3.0.101-108.220.1 |
+8
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-2026-52953Jun 24, 2026 · iommu/vt-d: Fix oops due to out of scope access28Monitor
- ← EarlierCVE-2026-52954Jun 24, 2026 · libceph: handle rbtree insertion error in decode_choose_args()30Monitor
- Later →CVE-2026-52956Jun 24, 2026 · libceph: Fix potential out-of-bounds access in __ceph_x_decrypt()30Monitor
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 | 0f3604cbe4df14c5e58288ac9f57511e726a222d | Vendor (CNA) |
| Linux Linux | 3f42508191e129ee6b5ea96578d5cab14f2a013a | Vendor (CNA) |
| Linux Linux | 4c79fc2d598694bda845b46229c9d48b65042970 | Vendor (CNA) |
| Linux Linux | 6e70ef53e818c53eab28d7b0026b7fd03dddaba5 | Vendor (CNA) |
| Linux Linux | cceb10023e76bc89f3fe9238ebd0ccab0fc7c7c5 | Vendor (CNA) |
| Linux Linux | ea0d42137f0c06da71e37ffc647aab4c5309599a | Vendor (CNA) |
| Linux Linux | ebe76d58a48a48031b98543d86c4cd30a825b622 | Vendor (CNA) |
| Linux Linux | fb176a99e4c1a5a8448a83d83d3606203ba81faa | Vendor (CNA) |
| debian:linux | 6.1.176-1 · Debian:12 | Package registry (OSV) |
| suse:kernel-64kb | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | Package registry (OSV) |
| suse:kernel-default | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise Micro 5.3 | Package registry (OSV) |
| suse:kernel-default-base | 5.14.21-150400.24.228.1.150400.24.116.1 · SUSE:Linux Enterprise Micro 5.3 | Package registry (OSV) |
| suse:kernel-docs | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | Package registry (OSV) |
| suse:kernel-livepatch-SLE15-SP4_Update_57 | 1-150400.9.3.1 · SUSE:Linux Enterprise Live Patching 15 SP4 | Package registry (OSV) |
| suse:kernel-livepatch-SLE15-SP5_Update_43 | 1-150500.11.5.1 · SUSE:Linux Enterprise Live Patching 15 SP5 | Package registry (OSV) |
| suse:kernel-obs-build | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | Package registry (OSV) |
| suse:kernel-rt | 5.14.21-150500.13.151.1 · SUSE:Linux Enterprise Micro 5.5 | Package registry (OSV) |
| suse:kernel-source | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise Micro 5.3 | Package registry (OSV) |
| suse:kernel-source-rt | 5.14.21-150500.13.151.1 · SUSE:Linux Enterprise Micro 5.5 | Package registry (OSV) |
| suse:kernel-syms | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | Package registry (OSV) |
| suse:kernel-zfcpdump | 5.14.21-150400.24.228.1 · SUSE:Linux Enterprise Server 15 SP4-LTSS | 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).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0440 · Jun 25, 2026(Linux Kernel Güvenlik Bildirimi)
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
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-125 · Out-of-bounds ReadCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (10 more)Show less
- git.kernel.org/stable/c/3f42508191e129ee6b5ea96578d5cab14f2a013a
- git.kernel.org/stable/c/4c79fc2d598694bda845b46229c9d48b65042970
- git.kernel.org/stable/c/6e70ef53e818c53eab28d7b0026b7fd03dddaba5
- git.kernel.org/stable/c/cceb10023e76bc89f3fe9238ebd0ccab0fc7c7c5
- git.kernel.org/stable/c/ea0d42137f0c06da71e37ffc647aab4c5309599a
- git.kernel.org/stable/c/ebe76d58a48a48031b98543d86c4cd30a825b622
- git.kernel.org/stable/c/fb176a99e4c1a5a8448a83d83d3606203ba81faa
- access.redhat.com/security/cve/CVE-2026-52955
- bugzilla.redhat.com/show_bug.cgi?id=2492328
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52955.json
Vendor advisories and official records. Exploit/PoC links are deliberately left out.