Okio: Incorrect Conversion between Numeric Types
CVE-2023-3635 is a high-severity incorrect conversion between numeric types vulnerability in Okio from Squareup, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 1.17.6, 3.4.0 as the first without the flaw, so updating Okio to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.25% chance of exploitation within 30 days, higher than 70% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Okio to 1.17.6 or 3.4.0, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Squareup | Okio | 0.5.0 up to, but not including, 1.17.6; 2.0.0 up to, but not including, 3.4.0 | 1.17.6, 3.4.0 |
Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 5.9 | Medium | CNA (jfrog.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
GzipSource does not handle an exception that might be raised when parsing a malformed gzip buffer. This may lead to denial of service of the Okio client when handling a crafted GZIP archive, by using the GzipSource class.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Conversion between Numeric Types
When converting from one data type to another, such as long to integer, data can be omitted or translated in a way that produces unexpected values. If the resulting values are used in a sensitive context, then dangerous behaviors may occur.
How developers prevent this class of flaw
- Avoid making conversion between numeric types. Always check for the allowed ranges.
More Incorrect Conversion between Numeric Types vulnerabilities (CWE-681)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Incorrect Conversion between Numeric Types vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 9.8 Critical severity
- 7.1 High severity
- 7.8 High severity
- 7.5 High severity
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