CVE-2020-28951
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedlibuci in OpenWrt before 18.06.9 and 19.x before 19.07.5 may encounter a use after free when using malicious package names. This is related to uci_parse_package in file.c and uci_strdup in util.c.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA use-after-free vulnerability in libuci's uci_parse_package (file.c) and uci_strdup (util.c) functions allows memory corruption when processing maliciously crafted package names, potentially enabling remote code execution. The vulnerability exists in OpenWRT versions prior to 18.06.9 and 19.x prior to 19.07.5.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 18.06.9>= 19.07.0, < 19.07.5CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify OpenWRT versionRun 'cat /etc/openwrt_version' or 'cat /etc/os-release' to retrieve the installed OpenWRT versionAffected if The version is less than 18.06.9 OR is 19.07.0 through 19.07.4
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Verify libuci library presenceCheck if libuci is installed by running 'uci' command or checking for the library file at /lib/libuci.so*'Affected if libuci is present and being used by the system
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Check UCI configuration parsing usageInspect any custom UCI configuration files or scripts that call 'uci parse' or process package names, particularly any that handle untrusted inputAffected if UCI configuration parsing handles external or untrusted package names
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Review custom package handlingSearch for any custom scripts or programs that call uci_parse_package or use UCI library functions to process package names from network input or external sourcesAffected if Custom code calls uci_parse_package or uci_strdup with potentially malicious package name input
A system is affected if it runs OpenWRT versions prior to 18.06.9 or between 19.07.0 and 19.07.4 and utilizes libuci to parse configuration packages from untrusted sources.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped18.06.919.07.5
Upgrade OpenWRT to version 18.06.9 or 19.07.5 or later to incorporate the patched libuci library, and verify UCI-based configuration functionality post-update.
OpenWrt 18.06.9 or 19.07.5 (depending on your current branch)
- 1. Backup your current OpenWrt configuration using the 'uci commit' command and backup utility, or by copying /etc/config/ files
- 2. Download the appropriate fixed OpenWrt firmware image for your device from the official OpenWrt download page (https://downloads.openwrt.org/)
- 3. For OpenWrt 18.06.x: upgrade to version 18.06.9; for OpenWrt 19.07.x: upgrade to version 19.07.5
- 4. Upload the firmware via the LuCI web interface under System > Backup/Flash Firmware, or use the sysupgrade command-line utility: 'sysupgrade -v /path/to/openwrt-firmware.bin'
- 5. After flashing, restore your configuration and verify libuci functionality
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation6.0 h
- Implementation12.0 h
- Testing10.0 h
- Review / QA6.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $9,504.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-28951 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2020-28951 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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