GHSA-gwfr-jfjf-92vv

Suggest an improvement
Source
https://github.com/advisories/GHSA-gwfr-jfjf-92vv
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-gwfr-jfjf-92vv/GHSA-gwfr-jfjf-92vv.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-gwfr-jfjf-92vv
Aliases
Published
2026-05-05T21:29:29Z
Modified
2026-09-10T03:51:05Z
Severity
  • 5.0 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L CVSS Calculator
  • 1.3 (Low) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P CVSS Calculator
Summary
Grav has Insecure Deserialization in File Cache
Details

Insecure Deserialization in File Cache

  • Severity: High
  • CWE: CWE-502
  • Location: system/src/Grav/Framework/Cache/Adapter/FileCache.php
  • Sink: unserialize($value, ['allowed_classes' => true])

Affected version(s)

  • Affected: >= 1.7.44 and <= 1.7.49.5 (verified in current codebase and changelog-covered releases).
  • Fixed: No upstream fix identified in the reviewed branch at the time of analysis.
  • Notes: Earlier 1.7.x releases may also be affected, but were not fully back-traced in this review.

Notes

allowed_classes => true allows object instantiation and does not constrain classes.

PoC (Primitive Demonstration)

Preconditions

  • Local PHP runtime.
  • Goal is to validate the deserialization primitive used in cache retrieval.

Steps

php -r '
class CacheWakeup { public function __wakeup(){ file_put_contents("/tmp/grav_filecache_poc.txt", "wakeup"); } }

$payload = serialize(new CacheWakeup());
unserialize($payload, ["allowed_classes" => true]);

echo file_exists("/tmp/grav_filecache_poc.txt") ? "FILECACHE_UNSERIALIZE_TRIGGERED\n" : "FILECACHE_UNSERIALIZE_NOT_TRIGGERED\n";
'

Expected Result

  • Output contains: FILECACHE_UNSERIALIZE_TRIGGERED.

Interpretation

This reproduces the same unsafe primitive used by FileCache::doGet(): unserialize($value, ['allowed_classes' => true]). If cache files are attacker-tampered, object magic methods may execute.

Exploit Preconditions

  • Cache file poisoning/tampering capability.

Recommendation

  • Avoid object deserialization in cache payloads.
  • Use non-object formats and integrity protection for cache files.

Maintainer note — fix applied (2026-04-24)

Fixed in Grav core on the 2.0 branch: commit c66dfeb5f — will ship in 2.0.0-beta.2.

What changed: Framework\Cache\Adapter\FileCache now HMAC-signs every cache payload with Security::getNonceKey() on write, and verifies the HMAC on read. Tampered, forged, or pre-upgrade files are treated as cache misses and unlinked instead of being unserialized. The on-disk format is now versioned:

v2
<expires>
<key>
<hmac-hex>
<serialized>

Existing caches rebuild transparently on first read. Note that Framework\Cache\Adapter\FileCache isn't wired into Grav's main cache path — Symfony's FilesystemAdapter is — but the class is reachable by plugin and downstream consumers, so the hardening applies defensively.

Files:

Database specific
{
    "cwe_ids":  [
        "CWE-20",
        "CWE-502"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-05-05T21:29:29Z",
    "nvd_published_at":  null,
    "severity":  "LOW"
}
References

Affected packages

Packagist / getgrav/grav

Package

Name
getgrav/grav
Purl
pkg:composer/getgrav/grav

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.0.0-beta.2

Affected versions

0.*
0.8.0
0.9.0
0.9.1
0.9.2
0.9.3
0.9.4
0.9.5
0.9.6
0.9.7
0.9.8
0.9.9
0.9.10
0.9.11
0.9.12
0.9.13
0.9.14
0.9.15
0.9.16
0.9.17
0.9.18
0.9.19
0.9.20
0.9.21
0.9.22
0.9.23
0.9.24
0.9.25
0.9.26
0.9.27
0.9.28
0.9.29
0.9.30
0.9.31
0.9.32
0.9.33
0.9.34
0.9.35
0.9.36
0.9.37
0.9.38
0.9.39
0.9.40
0.9.41
0.9.42
0.9.43
0.9.44
0.9.45
1.*
1.0.0-rc.1
1.0.0-rc.2
1.0.0-rc.3
1.0.0-rc.4
1.0.0-rc.5
1.0.0-rc.6
1.0.0
1.0.1
1.0.2
1.0.3
1.0.4
1.0.5
1.0.6
1.0.7
1.0.8
1.0.9
1.0.10
1.1.0-beta.1
1.1.0-beta.2
1.1.0-beta.3
1.1.0-beta.4
1.1.0-beta.5
1.1.0-rc.1
1.1.0-rc.2
1.1.0-rc.3
1.1.0
1.1.1
1.1.2
1.1.3
1.1.4
1.1.5
1.1.6
1.1.7
1.1.8
1.1.9-rc.1
1.1.9-rc.2
1.1.9-rc.3
1.1.9
1.1.10
1.1.11
1.1.12
1.1.13
1.1.14
1.1.15
1.1.16
1.1.17
1.2.0-rc.1
1.2.0-rc.2
1.2.0-rc.3
1.2.0
1.2.1
1.2.2
1.2.3
1.2.4
1.3.0-rc.1
1.3.0-rc.2
1.3.0-rc.3
1.3.0-rc.4
1.3.0-rc.5
1.3.0
1.3.1
1.3.2
1.3.3
1.3.4
1.3.5
1.3.6
1.3.7
1.3.8
1.3.9
1.3.10
1.4.0-beta.1
1.4.0-beta.2
1.4.0-beta.3
1.4.0-rc.1
1.4.0-rc.2
1.4.0
1.4.1
1.4.2
1.4.3
1.4.4
1.4.5
1.4.6
1.4.7
1.4.8
1.5.0-beta.1
1.5.0-beta.2
1.5.0-rc.1
1.5.0
1.5.1
1.5.2
1.5.3
1.5.4
1.5.5
1.5.6
1.5.7
1.5.8
1.5.9
1.5.10
1.6.0-beta.1
1.6.0-beta.2
1.6.0-beta.3
1.6.0-beta.4
1.6.0-beta.5
1.6.0-beta.6
1.6.0-beta.7
1.6.0-beta.8
1.6.0-rc.1
1.6.0-rc.2
1.6.0-rc.3
1.6.0-rc.4
1.6.0
1.6.1
1.6.2
1.6.3
1.6.4
1.6.5
1.6.6
1.6.7
1.6.8
1.6.9
1.6.10
1.6.11
1.6.12
1.6.13
1.6.14
1.6.15
1.6.16
1.6.17
1.6.18
1.6.19
1.6.20
1.6.21
1.6.22
1.6.23
1.6.24
1.6.25
1.6.26
1.6.27
1.6.28
1.6.29
1.6.30
1.6.31
1.7.0-beta.1
1.7.0-beta.2
1.7.0-beta.3
1.7.0-beta.4
1.7.0-beta.5
1.7.0-beta.6
1.7.0-beta.7
1.7.0-beta.8
1.7.0-beta.9
1.7.0-beta.10
1.7.0-rc.1
1.7.0-rc.2
1.7.0-rc.3
1.7.0-rc.4
1.7.0-rc.5
1.7.0-rc.6
1.7.0-rc.7
1.7.0-rc.8
1.7.0-rc.9
1.7.0-rc.10
1.7.0-rc.11
1.7.0-rc.12
1.7.0-rc.13
1.7.0-rc.14
1.7.0-rc.15
1.7.0-rc.16
1.7.0-rc.17
1.7.0-rc.18
1.7.0-rc.19
1.7.0-rc.20
1.7.0
1.7.1
1.7.3
1.7.4
1.7.5
1.7.6
1.7.7
1.7.8
1.7.9
1.7.10
1.7.12
1.7.13
1.7.14
1.7.15
1.7.16
1.7.17
1.7.18
1.7.19
1.7.20
1.7.21
1.7.22
1.7.23
1.7.24
1.7.25
1.7.26
1.7.26.1
1.7.27
1.7.27.1
1.7.28
1.7.29
1.7.29.1
1.7.30
1.7.31
1.7.32
1.7.33
1.7.34
1.7.35
1.7.36
1.7.37
1.7.37.1
1.7.38
1.7.39
1.7.39.1
1.7.39.2
1.7.39.3
1.7.39.4
1.7.40
1.7.41
1.7.41.1
1.7.41.2
1.7.42
1.7.42.1
1.7.42.2
1.7.42.3
1.7.43
1.7.44
1.7.45
1.7.46
1.7.47
1.7.48
1.7.49
1.7.49.1
1.7.49.2
1.7.49.3
1.7.49.4
1.7.49.5
1.7.51
1.7.52
1.7.53
1.7.53.1
1.7.53.2
1.7.53.3
1.8.0-beta.1
1.8.0-beta.2
1.8.0-beta.3
1.8.0-beta.4
1.8.0-beta.5
1.8.0-beta.6
1.8.0-beta.7
1.8.0-beta.8
1.8.0-beta.9
1.8.0-beta.10
1.8.0-beta.11
1.8.0-beta.12
1.8.0-beta.13
1.8.0-beta.14
1.8.0-beta.15
1.8.0-beta.16
1.8.0-beta.17
1.8.0-beta.18
1.8.0-beta.19
1.8.0-beta.20
1.8.0-beta.21
1.8.0-beta.22
1.8.0-beta.23
1.8.0-beta.24
1.8.0-beta.25
1.8.0-beta.26
1.8.0-beta.27
1.8.0-beta.28
1.8.0-beta.29
2.*
2.0.0-beta.1

Database specific

source
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-gwfr-jfjf-92vv/GHSA-gwfr-jfjf-92vv.json"