CVE-2026-43493: crypto: pcrypt - Fix handling of MAY_BACKLOG requests
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: 0.68% (FIRST EPSS); higher than 52.8% of all records.
- 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 1d7f07df450bac3301938fbc4251f2611be4084e, 46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a, 76641449b28979ebd6c02e9598367e119e385236.
Low priority for now. Upgrade to Linux Linux 1d7f07df450bac3301938fbc4251f2611be4084e, 46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a, 76641449b28979ebd6c02e9598367e119e385236 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: crypto: pcrypt - Fix handling of MAY_BACKLOG requests MAY_BACKLOG requests can return EBUSY. Handle them by checking for that value and filtering out EINPROGRESS notifications.
- Published
- May 19, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.6% · 52th percentile
- CWE
- CWE-390
Report tools
Action score
39
Low priority for now.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.6%
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 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 6.6.140
- linux linux kernel6.7 and later · before 6.12.86
- linux linux kernel6.13 and later · before 6.18.27
- linux linux kernel6.19 and later · before 7.0.4
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
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before ae7e95638d956d556d74b9abb9e780d3bd3dcd9eaffected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 1d7f07df450bac3301938fbc4251f2611be4084eaffected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 76641449b28979ebd6c02e9598367e119e385236affected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 9f1cbca178c03188e201ed175251372149bb25f2affected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before eb34e243df57e32f4c08fa191f3602ea19076276affected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 77d55bc8675ee851ed639dc9be77325a8024cf67affected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 46271895ddfb1ba41f89f7e0dffbe9c2bcf7380aaffected · git
- 5a1436beec5744029f3ac90b6fe71a698dcd6155 and later · before 915b692e6cb723aac658c25eb82c58fd81235110affected · 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 |
|---|---|---|---|
| AlmaLinux:10 | kernel | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel-matched | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-extra | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel-matched | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-extra | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-abi-stablelists | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-cross-headers | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel-matched | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules-core | before 6.12.0-211.49.1.el10_2 | 6.12.0-211.49.1.el10_2 |
+96
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-2026-43491May 19, 2026 · net: qrtr: ns: Limit the maximum server registration per node22Monitor
- ← EarlierCVE-2026-43492May 19, 2026 · lib/crypto: mpi: Fix integer underflow in mpi_read_raw_from_sgl()22Monitor
- Later →CVE-2026-43495May 21, 2026 · net: wwan: t7xx: validate port_count against message length in t7xx_port_enum_msg_handler35Monitor
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 | 1d7f07df450bac3301938fbc4251f2611be4084e | Vendor (CNA) |
| Linux Linux | 46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a | Vendor (CNA) |
| Linux Linux | 76641449b28979ebd6c02e9598367e119e385236 | Vendor (CNA) |
| Linux Linux | 77d55bc8675ee851ed639dc9be77325a8024cf67 | Vendor (CNA) |
| Linux Linux | 915b692e6cb723aac658c25eb82c58fd81235110 | Vendor (CNA) |
| Linux Linux | 9f1cbca178c03188e201ed175251372149bb25f2 | Vendor (CNA) |
| Linux Linux | ae7e95638d956d556d74b9abb9e780d3bd3dcd9e | Vendor (CNA) |
| Linux Linux | eb34e243df57e32f4c08fa191f3602ea19076276 | Vendor (CNA) |
| almalinux:kernel | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-core | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-core | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel-matched | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-core | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-extra | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel-matched | 6.12.0-211.49.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| debian:linux | 6.1.176-1 · Debian:12 | Package registry (OSV) |
| opensuse:kernel-source | 7.0.10-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:kernel-64k-debug-debuginfo | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-64k-debug-devel | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-64k-debug-devel-matched | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-64k-debuginfo | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-64k-devel | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-64k-devel-matched | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-debug-debuginfo | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:kernel-debug-devel | 0:6.12.0-211.49.1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
+6
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
- 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-390 · Detection of Error Condition Without ActionCVSS 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.
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 (8 more)Show less
- git.kernel.org/stable/c/46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a
- git.kernel.org/stable/c/76641449b28979ebd6c02e9598367e119e385236
- git.kernel.org/stable/c/77d55bc8675ee851ed639dc9be77325a8024cf67
- git.kernel.org/stable/c/915b692e6cb723aac658c25eb82c58fd81235110
- git.kernel.org/stable/c/9f1cbca178c03188e201ed175251372149bb25f2
- git.kernel.org/stable/c/ae7e95638d956d556d74b9abb9e780d3bd3dcd9e
- git.kernel.org/stable/c/eb34e243df57e32f4c08fa191f3602ea19076276
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.