CVE-2020-35906 json
futures_task::waker may cause a use-after-free if used on a type that isn't 'static
published 2020-09-04 6 y ago modified 2026-06-17 4 mo ago also GHSA-r93v-9p5q-vhpf , RUSTSEC-2020-0060 , EUVD-2022-5135
- cvss
- 7.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 43%
- public exploits
- 0
- none known
Summary
An issue was discovered in the futures-task crate before 0.3.6 for Rust. futures_task::waker may cause a use-after-free in a non-static type situation.
Patch / fix
- crates.io futures-task 0.3.6
- rust-lang futures-task 0.3.6
- github.com/rust-lang/futures-rs#2206 pull request
- rustsec.org/advisories/RUSTSEC-2020-0060.html advisory
Exploit prediction
0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- rustsec.org https://rustsec.org/advisories/RUSTSEC-2020-0060.html referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
| GitHub | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| OSV | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | futures-task | >=0.2.1, <0.3.6 >=0.2.2-0, <0.3.6 |
0.3.6 |
Classification
- Weakness
-
- CWE-416 Use After Free
References
-
rustsec.org
/advisories/RUSTSEC-2020-0060.html
web, exploit, patch, third-party-advisory, advisory
-
github.com
/rust-lang/futures-rs/pull/2206
web
-
nvd.nist.gov
/vuln/detail/CVE-2020-35906
advisory
-
github.com
/rust-lang/futures-rs
package
-
crates.io
/crates/futures-task
package
Sources
- CVE List CVE-2020-35906
- GitHub Advisory GHSA-r93v-9p5q-vhpf
- NVD CVE-2020-35906
- OSV RUSTSEC-2020-0060
Fencer Vulns 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.