CVE-2026-1998: micropython
Vulnerability summary
CVE-2026-1998 is a medium (CVSS 5.5) vulnerability in micropython. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 12.8% of scored vulnerabilities. 2 public exploits are recorded.
Timeline
- 06-02-2026PublishedVulnerability first disclosed.
- 23-02-2026Last modifiedVulnerability information updated.
Description
A flaw has been found in micropython up to 1.27.0. This vulnerability affects the function mp_import_all of the file py/runtime.c. This manipulation causes memory corruption. The attack needs to be launched locally. The exploit has been published and may be used. Patch name: 570744d06c5ba9dba59b4c3f432ca4f0abd396b6. It is suggested to install a patch to address this issue.
CVSS metrics
10 scores · 4 sources · 4 versions- OSV · UbuntuEcosystem advisory · calculated4.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
- NVDNIST1.9LowCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/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:XDiffers
- CVE.orgCNA3.3LowCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:CDiffers
- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- NVDNIST1.7LowAV:L/AC:L/Au:S/C:N/I:N/A:P
EPSS trend
Probability
0.23%
Chance of exploitation in the next 30 days
Percentile
13%
Versus all other CVEs
30-day change
+0.02 pp
From 0.21% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
2 foundMicropython
Maturity: poc
Exploit Reference (vuldb.com)
Maturity: unknown
Weaknesses
CWE · root cause- CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
Opensuse2 products
- micropython&distro=openSUSE Leap 16.0< 1.26.1-bp160.1.1
- micropython&distro=openSUSE Tumbleweed< 1.26.1-2.1
Debian1 product
- micropythonAll versions (No fix recorded)
Micropython1 product
- micropython≤ 1.27.0
Ubuntu1 product
- micropythonAll versions (No fix recorded)
4 vendors · 5 products
