CVE-2026-56254
capacitor-updater - End-to-End Encryption Bypass via Private Key Distribution
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
8.3
capacitor-updater - End-to-End Encryption Bypass via Private Key Distribution
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
- Record
CVE-2026-56254- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N - CVSS 3.1
- 7.0 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-320
- Updated
- 2026-11-02
EUVDEUVD-2026-42879
8.3
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
- Record
EUVD-2026-42879- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-v24w-qp6p-4wjw
8.3
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme...
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
- Record
GHSA-v24w-qp6p-4wjw- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.0 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L - Updated
- 2026-11-02
NVD
8.3
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
- Record
CVE-2026-56254- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.0 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-320
- Updated
- 2026-11-02
OSV
8.3
capacitor-updater - End-to-End Encryption Bypass via Private Key Distribution
In @capgo/capacitor-updater (Cap-go/capgo) before 12.128.2, the end-to-end encryption scheme distributes the private key to each device that downloads the app. Because the public key can be derived from the private key, an attacker performing a man-in-the-middle attack or compromising the Capgo server can create a validly signed update bundle and cause devices to install an update not produced by the original app maker.
- Record
CVE-2026-56254- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-320
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-56254 is a high vulnerability (CVSS 8.3) in Capacitor-updater, published July 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 9th percentile. No source names a fixed version.
References
github.com/Cap-go/capgo/security/advisories/GHSA-j2f4-4pfc-p8rx
vulncheck.com/advisories/capacitor-updater-end-to-end-encryption-bypass-via-private-key-distribution
nvd.nist.gov/vuln/detail/CVE-2026-56254
github.com/advisories/GHSA-v24w-qp6p-4wjw
github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56254.json