CyberSecBulletin
CVE-2022-39256NVD status: Modified

C1-CMS-Foundation: Deserialization of Untrusted Data

CVE-2022-39256 is a high-severity deserialization of untrusted data vulnerability in C1-CMS-Foundation from Orckestra, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected C1-CMS-Foundation versions: < 6.13. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.66% chance of exploitation within 30 days, higher than 77% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update C1 CMS to 6.13 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
OrckestraC1-CMS-Foundation< 6.13Not stated
OrckestraC1 CMSbefore 6.136.13

Version data comes from the organisation that assigned the CVE. 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
LowA basic user account is enough.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.0CriticalCNA (github.com)
CVSS 3.18.0HighNVD

Official description

Orckestra C1 CMS is a .NET based Web Content Management System. A vulnerability in versions prior to 6.13 allows remote attackers to execute arbitrary code on affected installations of Orckestra C1 CMS. Authentication is required to exploit this vulnerability. The authenticated user may perform the actions unknowingly by visiting a specially crafted site. This issue is patched in C1 CMS v6.13. There are no known workarounds.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Other vulnerabilities in C1-CMS-Foundation

All C1-CMS-Foundation vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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