Security readout for executives and security teams
Plain-English summary
hyper, a Rust HTTP library, mishandled oversized chunked transfer sizes before version 0.14.10. The flaw can cause integer overflow during HTTP decoding, leading to possible data loss. In specific proxy setups, it may also contribute to request smuggling or desynchronization.
Executive priority
Treat as moderate priority. Patch during dependency maintenance, with faster handling for internet-facing Rust HTTP services behind proxies because impact may include availability loss or request desynchronization.
Technical view
CVE-2021-32714 is a CWE-190 integer overflow in hyper server and client chunked Transfer-Encoding decoding. Risk increases when an upstream HTTP proxy accepts chunk sizes larger than hyper supports. The published fix is hyper 0.14.10.
Likely exposure
Exposure is limited to applications using hyper versions before 0.14.10, directly or through dependencies. Internet-facing HTTP services and deployments behind upstream proxies are the main review targets.
Exploitation context
The bundle does not show active exploitation, and KEV is false. Exploitation is high complexity and depends on oversized chunk handling, especially proxy and hyper parsing differences.
Researcher notes
Focus analysis on dependency resolution and proxy boundary behavior. The evidence identifies hyper before 0.14.10 only; it does not establish active exploitation or additional affected products.
Mitigation direction
- Upgrade hyper to version 0.14.10 or later.
- Reject requests containing Transfer-Encoding where operationally feasible.
- Ensure upstream proxies reject chunk sizes exceeding 64-bit unsigned integer limits.
- Check the hyper advisory for any environment-specific guidance.
Validation and detection
- Inventory Rust services and dependency lockfiles for hyper usage.
- Confirm resolved hyper versions are 0.14.10 or later.
- Review upstream proxy behavior for chunked Transfer-Encoding limits.
- Identify internet-facing services using vulnerable hyper versions.
- Document any temporary Transfer-Encoding filtering exceptions.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-190: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-32714 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H2.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.9MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/hyperium/hyper/security/advisories/GHSA-5h46-h7hh-c6x9CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Integer Overflow or Wraparound
Integer Overflow or Wraparound represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.