PHPPresentation: Deserialization of Untrusted Data
CVE-2026-114403 is a high-severity deserialization of untrusted data vulnerability in PHPPresentation from PHPOffice, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected PHPPresentation versions: 1.2.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.7% chance of exploitation within 30 days, higher than 54% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of PHPPresentation you run against the affected versions below, and install the vendor's latest release.
- 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 |
|---|---|---|---|
| PHPOffice | PHPPresentation | 1.2.0 and earlier | Not stated |
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
- HighSuccess depends on conditions outside the attacker's control.
- 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
- 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:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.2 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 8.1 | High | CNA (vulncheck.com) |
Official description
PHPOffice PHPPresentation through 1.2.0 contains an insecure deserialization vulnerability that allows attackers to instantiate arbitrary PHP objects by supplying a crafted presentation file. Attackers can upload a ZIP containing PhpPresentation.xml that IOFactory::load passes to unserialize(), enabling gadget-chain code execution, file writes, or denial of service.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- github.com/PHPOffice/PHPPresentation
- github.com/PHPOffice/PHPPresentation/blob/1.2.0/src/PhpPresentation/IOFactory.php#L39
- github.com/PHPOffice/PHPPresentation/blob/1.2.0/src/PhpPresentation/Reader/Serialized.php#L77-L109
- hackmd.io/@leediay/multiple_vulnerable_phppresentation
- vulncheck.com/advisories/phpoffice-phppresentation-through-1.2.0-deserialization-via-reader-serialized-load
Recent Deserialization of Untrusted Data vulnerabilities
- 7.2 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.7 High severity
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