CVE-2020-18378
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s...
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
CVE-2020-18378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
CVE List
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
CVE-2020-18378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
EUVDEUVD-2020-10302
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
EUVD-2020-10302- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-vj54-ff4j-gq2v
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s...
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
GHSA-vj54-ff4j-gq2v- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
CVE-2020-18378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2020-18378
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
DEBIAN-CVE-2020-18378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2020-18378
6.5
A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in wasm/wasm-s-parser.c in Binaryen 1.38.26. A crafted wasm input can cause a segmentation fault, leading to denial-of-service, as demonstrated by wasm-as.
- Record
UBUNTU-CVE-2020-18378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
binaryenDebian:12 |
before 68-1 | 68-1 |
binaryenDebian:13 |
before 68-1 | 68-1 |
binaryenDebian:14 |
before 68-1 | 68-1 |
binaryenUbuntu:20.04:LTS |
All versions, plus listed versions 89-190-191-1 |
None known |
binaryenUbuntu:22.04:LTS |
All versions, plus listed versions 99-3105-1 |
None known |
binaryenUbuntu:24.04:LTS |
All versions, plus listed versions 108-1 |
None known |
binaryenUbuntu:25.10 |
All versions, plus listed versions 120-3120-4 |
None known |
binaryenUbuntu:26.10 |
All versions, plus listed versions 120-4build1130-2130-3131-2 |
None known |
binaryenUbuntu:26.04:LTS |
All versions, plus listed versions 120-4120-4build1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-18378 is a medium vulnerability (CVSS 6.5) in Webassembly Binaryen, published August 22, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.61%, the 49th percentile. Fixed in binaryen 68-1.