CVE-2019-3557

Description

The implementations of streams for bz2 and php://output improperly implemented their readImpl functions, returning -1 consistently. This behavior caused some stream functions, such as stream_get_line, to trigger an out-of-bounds read when operating on such malformed streams. The implementations were updated to return valid values consistently. This affects all supported versions of HHVM (3.30 and 3.27.4 and below).

Category

9.8
CVSS
Severity: Critical
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.61%
Vendor Advisory hhvm.com
Affected: Facebook HHVM
Published at:
Updated at:

References

Link Tags
https://hhvm.com/blog/2019/01/14/hhvm-3.30.2.html vendor advisory
https://github.com/facebook/hhvm/commit/6e4dd9ec3f14b48170fc45dc9d13a3261765f994 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2019-3557?
CVE-2019-3557 has been scored as a critical severity vulnerability.
How to fix CVE-2019-3557?
To fix CVE-2019-3557, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-3557 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2019-3557 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-3557?
CVE-2019-3557 affects Facebook HHVM.
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