Description
The fb_unserialize function did not impose a depth limit for nested deserialization. That meant a maliciously constructed string could cause deserialization to recurse, leading to stack exhaustion. This issue affected HHVM prior to v4.32.3, between versions 4.33.0 and 4.56.0, 4.57.0, 4.58.0, 4.58.1, 4.59.0, 4.60.0, 4.61.0, 4.62.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| HHVM | 4.62.0, 4.61.0, 4.60.0, 4.59.0, 4.58.0 – < unspecified, 4.57.0, 4.33.0 – < unspecified, unspecified – < 4.32.3 | unspecified |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | hhvm | No fix yet | — |
| Ubuntu 16.04 LTS | hhvm | No fix yet | — |