GHSA-w4cm-gvhj-cgw6

Suggest an improvement
Source
https://github.com/advisories/GHSA-w4cm-gvhj-cgw6
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-w4cm-gvhj-cgw6/GHSA-w4cm-gvhj-cgw6.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-w4cm-gvhj-cgw6
Aliases
Published
2026-09-23T21:23:58Z
Modified
2026-09-23T21:45:08Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
Jawn: Quadratic parsing effort in AsyncParser
Details

AsyncParser can be forced to perform O(n^2) work on the length of the input. When a single JSON token arrives across many small chunks, each absorb call rescans the incomplete token from the start.

Impact

Denial of service via CPU exhaustion when parsing untrusted JSON.

Preconditions:

  • Application uses AsyncParser
  • Attacker can send large tokens with control over chunk sizes.

Patches

Fixed in jawn-parser-1.7.0.

Workarounds

If you can't upgrade immediately:

  • Use the synchronous Parser.
  • Buffer incoming bytes into larger chunks before calling absorb
Database specific 
{
    "cwe_ids":  [
        "CWE-400",
        "CWE-407"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-09-23T21:23:58Z",
    "nvd_published_at":  null,
    "severity":  "HIGH"
}
References

Affected packages

Maven / org.typelevel:jawn-parser_2.12

Package

Name
org.typelevel:jawn-parser_2.12
View open source insights on deps.dev
Purl
pkg:maven/org.typelevel/jawn-parser_2.12

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.7.0

Affected versions

0.*
0.14.0
0.14.1
0.14.2
0.14.3
1.*
1.0.0-RC1
1.0.0-RC2
1.0.0-RC3
1.0.0-RC4
1.0.0
1.0.1
1.0.2
1.0.3
1.1.0
1.1.1
1.1.2
1.2.0
1.3.0
1.3.1
1.3.2
1.4.0
1.5.0
1.5.1
1.6.0

Database specific

last_known_affected_version_range 
"<= 1.6.0"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-w4cm-gvhj-cgw6/GHSA-w4cm-gvhj-cgw6.json"

Maven / org.typelevel:jawn-parser_2.13

Package

Name
org.typelevel:jawn-parser_2.13
View open source insights on deps.dev
Purl
pkg:maven/org.typelevel/jawn-parser_2.13

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.7.0

Affected versions

0.*
0.14.2
0.14.3
1.*
1.0.0-RC1
1.0.0-RC2
1.0.0-RC3
1.0.0-RC4
1.0.0
1.0.1
1.0.2
1.0.3
1.1.0
1.1.1
1.1.2
1.2.0
1.3.0
1.3.1
1.3.2
1.4.0
1.5.0
1.5.1
1.6.0

Database specific

last_known_affected_version_range 
"<= 1.6.0"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-w4cm-gvhj-cgw6/GHSA-w4cm-gvhj-cgw6.json"

Maven / org.typelevel:jawn-parser_3

Package

Name
org.typelevel:jawn-parser_3
View open source insights on deps.dev
Purl
pkg:maven/org.typelevel/jawn-parser_3

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.7.0

Affected versions

1.*
1.1.2
1.2.0
1.3.0
1.3.1
1.3.2
1.4.0
1.5.0
1.5.1
1.6.0

Database specific

last_known_affected_version_range 
"<= 1.6.0"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-w4cm-gvhj-cgw6/GHSA-w4cm-gvhj-cgw6.json"