CVE-2020-1893
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory,...
CVE-2020-1893 is a high vulnerability (CVSS 7.5) in Facebook Hhvm, published March 3, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.15%, the 67th percentile. No source names a fixed version.
- Severity
- 7.5 HighCVSS 3.1, NVD
- Exploit chance
- 1.15%EPSS, 67th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
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
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
hhvmUbuntu:16.04:LTS | All versions, plus listed versions 3.11.0+dfsg-13.11.1+dfsg-13.11.1+dfsg-1ubuntu1 | None known |
hhvmUbuntu:18.04:LTS | All versions, plus listed versions 3.21.0+dfsg-23.21.0+dfsg-2build13.21.0+dfsg-2build23.21.0+dfsg-2build33.21.0+dfsg-2ubuntu2 | None known |
What each source reports
NVD Score used 7.5
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
CVE-2020-1893- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-125
- Updated
- 2026-11-02
CVE ListNo score
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
CVE-2020-1893- Weakness
- CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2020-12719No score
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
EUVD-2020-12719- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-m8q8-334f-8qxgNo score
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory,...
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
GHSA-m8q8-334f-8qxg- Updated
- 2026-11-02
OSV 7.5
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
CVE-2020-1893- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-04
OSVUBUNTU-CVE-2020-1893 7.5
Insufficient boundary checks when decoding JSON in TryParse reads out of bounds memory, potentially leading to DOS. This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
- Record
UBUNTU-CVE-2020-1893- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.