In the Linux kernel, the following vulnerability has been resolved:
mm, shmem: prevent infinite loop on truncate race
When truncating a large swap entry, shmem_free_swap() returns 0 when the
entry's index doesn't match the given index due to lookup alignment. The
failure fallback path checks if the entry crosses the end border and
aborts when it happens, so truncate won't erase an unexpected entry or
range. But one scenario was ignored.
When index points to the middle of a large swap entry, and the large
swap entry doesn't go across the end border, find_get_entries() will
return that large swap entry as the first item in the batch with
indices[0] equal to index. The entry's base index will be smaller
than indices[0], so shmem_free_swap() will fail and return 0 due to the
"base < index" check. The code will then call shmem_confirm_swap(), get
the order, check if it crosses the END boundary (which it doesn't), and
retry with the same index.
The next iteration will find the same entry again at the same index with
same indices, leading to an infinite loop.
Fix this by retrying with a round-down index, and abort if the index is
smaller than the truncate range.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
- EG Severity
- Not assessed: no CVSS publishedA missing CVSS is not a severity of zero.
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-26). 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
- No SSVC decision: EchelonGraph has not assessed this CVECISA 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 BOD 26-04 block below.
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's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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