In the Linux kernel, the following vulnerability has been resolved:
PCI: Check ROM header and data structure addr before accessing
We meet a crash when running stress-ng on x86_64 machine:
BUG: unable to handle page fault for address: ffa0000007f40000
RIP: 0010:pci_get_rom_size+0x52/0x220
Call Trace:
pci_map_rom+0x80/0x130
pci_read_rom+0x4b/0xe0
kernfs_file_read_iter+0x96/0x180
vfs_read+0x1b1/0x300
Our analysis reveals that the ROM space's start address is
0xffa0000007f30000, and size is 0x10000. Because of broken ROM space,
before calling readl(pds), the pds's value is 0xffa0000007f3ffff, which is
already pointed to the ROM space end, invoking readl() would read 4 bytes
therefore cause an out-of-bounds access and trigger a crash. Fix this by
adding image header and data structure checking.
We also found another crash on arm64 machine:
Unable to handle kernel paging request at virtual address ffff8000dd1393ff
Mem abort info:
ESR = 0x0000000096000021
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x21: alignment fault
The call trace is the same with x86_64, but the crash reason is that the
data structure addr is not aligned with 4, and arm64 machine report
"alignment fault". Fix this by adding alignment checking.
[bhelgaas: shorten function names, wrap comments]
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.7): severity, escalated by confirmed exploitation. This CVE's 7.7 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.7 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it