CVE-2025-29776
Azle calling `setTimer` causes infinite loop of timers
Azle is a WebAssembly runtime for TypeScript and JavaScript on ICP. Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer. The infinite loop will occur with any valid invocation of setTimer. The problem has been fixed as of Azle version 0.30.0. As a workaround, if a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Azle calling `setTimer` causes infinite loop of timers
Azle is a WebAssembly runtime for TypeScript and JavaScript on ICP. Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer. The infinite loop will occur with any valid invocation of setTimer. The problem has been fixed as of Azle version 0.30.0. As a workaround, if a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
CVE-2025-29776- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Weakness
- CWE-835
- Updated
- 2026-11-02
EUVDEUVD-2025-6418
Azle is a WebAssembly runtime for TypeScript and JavaScript on ICP. Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer. The infinite loop will occur with any valid invocation of setTimer. The problem has been fixed as of Azle version 0.30.0. As a workaround, if a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
EUVD-2025-6418- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xc76-5pf9-mx8m
In Azle, calling `setTimer` causes infinite loop of timers
Impact
Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer.
The infinite loop will occur with any valid invocation of setTimer.
Patches
The problem has been fixed as of Azle version 0.30.0.
Workarounds
If a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
GHSA-xc76-5pf9-mx8m- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Weakness
- CWE-835
- Updated
- 2026-11-02
NVD
Azle is a WebAssembly runtime for TypeScript and JavaScript on ICP. Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer. The infinite loop will occur with any valid invocation of setTimer. The problem has been fixed as of Azle version 0.30.0. As a workaround, if a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
CVE-2025-29776- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/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 - Weakness
- CWE-835
- Updated
- 2026-11-02
OSV
Azle calling `setTimer` causes infinite loop of timers
Azle is a WebAssembly runtime for TypeScript and JavaScript on ICP. Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer. The infinite loop will occur with any valid invocation of setTimer. The problem has been fixed as of Azle version 0.30.0. As a workaround, if a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
CVE-2025-29776- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Weakness
- CWE-835
- Updated
- 2026-11-05
OSVGHSA-xc76-5pf9-mx8m
In Azle, calling `setTimer` causes infinite loop of timers
Impact
Calling setTimer in Azle versions 0.27.0, 0.28.0, and 0.29.0 causes an immediate infinite loop of timers to be executed on the canister, each timer attempting to clean up the global state of the previous timer.
The infinite loop will occur with any valid invocation of setTimer.
Patches
The problem has been fixed as of Azle version 0.30.0.
Workarounds
If a canister is caught in this infinite loop after calling setTimer, the canister can be upgraded and the timers will all be cleared, thus ending the loop.
- Record
GHSA-xc76-5pf9-mx8m- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Weakness
- CWE-835
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
azlenpm |
0.27.0 up to 0.30.0 | 0.30.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-29776 is a high vulnerability (CVSS 8.7) in Demergent-labs Azle, published March 14, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.38%, the 32nd percentile. Fixed in azle 0.30.0.
References
github.com/demergent-labs/azle/security/advisories/GHSA-xc76-5pf9-mx8m
nvd.nist.gov/vuln/detail/CVE-2025-29776