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Fencer Intel
medium 4.7

CVE-2020-35905 json

MutexGuard::map can cause a data race in safe code

published 6y ago modified 4mo ago also GHSA-rh4w-94hh-9943 , RUSTSEC-2020-0059 , EUVD-2022-5172

cvss
4.7
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits
0
none known

Summary

An issue was discovered in the futures-util crate before 0.3.7 for Rust. MutexGuard::map can cause a data race for certain closure situations (in safe code).

Patch / fix

  • crates.io futures-util 0.3.7
  • rust-lang future-utils 0.3.7

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Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • rustsec.org https://rustsec.org/advisories/RUSTSEC-2020-0059.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 4.7 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 1.9 AV:L/AC:M/Au:N/C:N/I:N/A:P
OSV 3.1 4.7 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 4.7 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
crates.io futures-util
>=0.3.2, <0.3.7
0.3.7

Classification

Weakness
  • CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.