In the Linux kernel, the following vulnerability has been resolved:
page_pool: Fix PP_MAGIC_MASK to avoid crashing on some 32-bit arches
Helge reported that the introduction of PP_MAGIC_MASK let to crashes on
boot on his 32-bit parisc machine. The cause of this is the mask is set
too wide, so the page_pool_page_is_pp() incurs false positives which
crashes the machine.
Just disabling the check in page_pool_is_pp() will lead to the page_pool
code itself malfunctioning; so instead of doing this, this patch changes
the define for PP_DMA_INDEX_BITS to avoid mistaking arbitrary kernel
pointers for page_pool-tagged pages.
The fix relies on the kernel pointers that alias with the pp_magic field
always being above PAGE_OFFSET. With this assumption, we can use the
lowest bit of the value of PAGE_OFFSET as the upper bound of the
PP_DMA_INDEX_MASK, which should avoid the false positives.
Because we cannot rely on PAGE_OFFSET always being a compile-time
constant, nor on it always being >0, we fall back to disabling the
dma_index storage when there are not enough bits available. This leaves
us in the situation we were in before the patch in the Fixes tag, but
only on a subset of architecture configurations. This seems to be the
best we can do until the transition to page types in complete for
page_pool pages.
v2:
- Make sure there's at least 8 bits available and that the PAGE_OFFSET
bit calculation doesn't wrap
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.8 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 (model v2026.06.15, score date 2026-11-03). 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 low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (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