Answer in brief
CVE-2026-63942 records a Unknown severity vulnerability in parport: Fix race between port and client registration. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-63942 records a Unknown severity vulnerability in parport: Fix race between port and client registration. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=6fa45a22689722dac9f0e90c0931d4b34b334ede <f3378b0d7bd4605de89b083b2900788157a181cc || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <290f515c5e3b3900bc2fe24f179999fd08d23bfa || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <d16548be2ea5058227d79799e81dab61c9bca8ec || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <15b1723c1472e802f9f7e69ae4e64f7dbf588848 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <51026cff1f4f3b762a0b5a07c727bd59cef45320 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <74d6aae1df45d3414178986be743f946988fddf6 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <a1e81b58da0179531bedf0b9f2811f5f992d5c4b || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <ef15ccbb3e8640a723c42ad90eaf81d66ae02017 | f3378b0d7bd4605de89b083b2900788157a181cc, 290f515c5e3b3900bc2fe24f179999fd08d23bfa, d16548be2ea5058227d79799e81dab61c9bca8ec, 15b1723c1472e802f9f7e69ae4e64f7dbf588848, 51026cff1f4f3b762a0b5a07c727bd59cef45320, 74d6aae1df45d3414178986be743f946988fddf6, a1e81b58da0179531bedf0b9f2811f5f992d5c4b, ef15ccbb3e8640a723c42ad90eaf81d66ae02017 |
| Linux/Linuxgeneric | 4.2 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: parport: Fix race between port and client registration The parport subsystem registers port devices before they are fully initialised, resulting in a race condition where client drivers such as lp can attach to ports that are not completely initialised or even being torn down. When the port and client drivers are built as modules and loaded around the same time during boot, this occasionally results in a crash. I was able to make this happen reliably in a VM with a PC-style parallel port by patching parport_pc to fail probing: > --- a/drivers/parport/parport_pc.c > +++ b/drivers/parport/parport_pc.c > @@ -2069,7 +2069,7 @@ static struct parport *__parport_pc_probe_port(unsigned long int base, > if (!p) > goto out3; > > - base_res = request_region(base, 3, p->name); > + base_res = NULL; > if (!base_res) > goto out4; > and then running: while true; do modprobe lp & modprobe parport_pc wait rmmod lp parport_pc done for a few seconds. In the long term I think port registration should be changed to put the call to device_add() inside parport_announce_port(), but since the latter currently cannot fail this will require changing all port drivers. For now, add a flag to indicate whether a port has been "announced" and only try to attach client drivers to ports when the flag is set.
Quoted source text, attributed separately from HOL analysis.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=6fa45a22689722dac9f0e90c0931d4b34b334ede <f3378b0d7bd4605de89b083b2900788157a181cc || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <290f515c5e3b3900bc2fe24f179999fd08d23bfa || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <d16548be2ea5058227d79799e81dab61c9bca8ec || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <15b1723c1472e802f9f7e69ae4e64f7dbf588848 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <51026cff1f4f3b762a0b5a07c727bd59cef45320 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <74d6aae1df45d3414178986be743f946988fddf6 || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <a1e81b58da0179531bedf0b9f2811f5f992d5c4b || >=6fa45a22689722dac9f0e90c0931d4b34b334ede <ef15ccbb3e8640a723c42ad90eaf81d66ae02017 | f3378b0d7bd4605de89b083b2900788157a181cc, 290f515c5e3b3900bc2fe24f179999fd08d23bfa, d16548be2ea5058227d79799e81dab61c9bca8ec, 15b1723c1472e802f9f7e69ae4e64f7dbf588848, 51026cff1f4f3b762a0b5a07c727bd59cef45320, 74d6aae1df45d3414178986be743f946988fddf6, a1e81b58da0179531bedf0b9f2811f5f992d5c4b, ef15ccbb3e8640a723c42ad90eaf81d66ae02017 |
| Linux/Linuxgeneric | 4.2 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: parport: Fix race between port and client registration The parport subsystem registers port devices before they are fully initialised, resulting in a race condition where client drivers such as lp can attach to ports that are not completely initialised or even being torn down. When the port and client drivers are built as modules and loaded around the same time during boot, this occasionally results in a crash. I was able to make this happen reliably in a VM with a PC-style parallel port by patching parport_pc to fail probing: > --- a/drivers/parport/parport_pc.c > +++ b/drivers/parport/parport_pc.c > @@ -2069,7 +2069,7 @@ static struct parport *__parport_pc_probe_port(unsigned long int base, > if (!p) > goto out3; > > - base_res = request_region(base, 3, p->name); > + base_res = NULL; > if (!base_res) > goto out4; > and then running: while true; do modprobe lp & modprobe parport_pc wait rmmod lp parport_pc done for a few seconds. In the long term I think port registration should be changed to put the call to device_add() inside parport_announce_port(), but since the latter currently cannot fail this will require changing all port drivers. For now, add a flag to indicate whether a port has been "announced" and only try to attach client drivers to ports when the flag is set.
Quoted source text, attributed separately from HOL analysis.