Description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix NULL dereference in nfs3svc_encode_getaclres
In error cases the dentry may be NULL.
Before 20798dfe249a, the encoder also checked dentry and
d_really_is_positive(dentry), but that looks like overkill to me--zero
status should be enough to guarantee a positive dentry.
This isn't the first time we've seen an error-case NULL dereference
hidden in the initialization of a local variable in an xdr encoder. But
I went back through the other recent rewrites and didn't spot any
similar bugs.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.13 | 5.13.4 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | linux-riscv +20 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +26 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
Advisories 4
- SSA-265688 SSA-265688: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1 Siemens ProductCERT · Oct 13, 2026
- ICSA-24-102-01 Siemens SIMATIC S7-1500 TM MFP CISA ICS & IT advisories · May 14, 2026
- ICSA-25-226-07 Siemens Third-Party Components in SINEC OS CISA ICS & IT advisories · Feb 25, 2026
- SSA-355557 SSA-355557: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.2 Siemens ProductCERT · Feb 24, 2026