# CVE-2026-49740: TYPO3 CMS - Insecure Deserialization in Core API > An attacker with local write access to storage can inject serialized payloads to achieve remote code execution via PHP object injection. - **Severity:** Medium 6.3 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 9 Jun 2026 - **Updated:** 15 Jul 2026 - **Also known as:** GHSA-c78m-c52x-jgwp ## What is CVE-2026-49740? CVE-2026-49740 is a medium-severity unsafe deserialization vulnerability in TYPO3 CMS, published on 9 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description TYPO3's cache frontend (VariableFrontend) and persistent key-value store (Registry) deserialized PHP payloads without integrity validation or class restrictions. An attacker with write access to the underlying storage backend (cache store or sys_registry database table) could inject a crafted serialized payload to trigger PHP Object Injection, potentially exploiting a gadget chain to achieve Remote Code Execution or other high-impact effects. Exploiting this vulnerability requires direct local write access to the storage, such as the SQL database or file system. This issue affects TYPO3 CMS versions before 10.4.57, 11.0.0-11.5.50, 12.0.0-12.4.45, 13.0.0-13.4.30 and 14.0.0-14.3.2. Weakness: CWE-502 (Deserialization of Untrusted Data) ## Which versions are affected by CVE-2026-49740? 10 open source packages ship an affected version, including typo3/cms-core. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `typo3/cms-core` | Packagist | All versions | 10.4.57 | | `typo3/cms-core` | Packagist | All versions | 10.4.57 | | `typo3/cms-core` | Packagist | From 11.0.0 | 11.5.51 | | `typo3/cms-core` | Packagist | From 11.0.0 | 11.5.51 | | `typo3/cms-core` | Packagist | From 12.0.0 | 12.4.46 | | `typo3/cms-core` | Packagist | From 12.0.0 | 12.4.46 | | `typo3/cms-core` | Packagist | From 13.0.0 | 13.4.31 | | `typo3/cms-core` | Packagist | From 13.0.0 | 13.4.31 | | `typo3/cms-core` | Packagist | From 14.0.0 | 14.3.3 | | `typo3/cms-core` | Packagist | From 14.0.0 | 14.3.3 | ## How do I fix CVE-2026-49740? Upgrade typo3/cms-core to a fixed version for your release line: 10.4.57, 11.5.51, 12.4.46 or 13.4.31. ## Is CVE-2026-49740 being exploited? There is no known exploitation of CVE-2026-49740 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-49740 and fix it if it is affected. What it is: CVE-2026-49740 is a medium-severity unsafe deserialization vulnerability in TYPO3 CMS, published on 9 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-49740 in the wild and no public exploit code. Affected packages and fixed versions: - typo3/cms-core (Packagist): affected all versions; fixed in 10.4.57 - typo3/cms-core (Packagist): affected all versions; fixed in 10.4.57 - typo3/cms-core (Packagist): affected from 11.0.0; fixed in 11.5.51 - typo3/cms-core (Packagist): affected from 11.0.0; fixed in 11.5.51 - typo3/cms-core (Packagist): affected from 12.0.0; fixed in 12.4.46 - typo3/cms-core (Packagist): affected from 12.0.0; fixed in 12.4.46 - typo3/cms-core (Packagist): affected from 13.0.0; fixed in 13.4.31 - typo3/cms-core (Packagist): affected from 13.0.0; fixed in 13.4.31 - typo3/cms-core (Packagist): affected from 14.0.0; fixed in 14.3.3 - typo3/cms-core (Packagist): affected from 14.0.0; fixed in 14.3.3 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-49740/ (Markdown: https://insights.sbomify.com/CVE-2026-49740/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49740 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49740 - OSV: https://osv.dev/vulnerability/CVE-2026-49740 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-49740/ Summaries are generated and may contain mistakes; the official description above is the record.