CVE-2021-30342
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 · uneditedImproper integrity check can lead to race condition between tasks PDCP and RRC? after a valid RRC Command packet has been received in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Voice & Music, Snapdragon Wearables
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 · moderate confidenceA race condition exists between PDCP (Packet Data Convergence Protocol) and RRC (Radio Resource Control) tasks due to improper integrity validation. After a valid RRC Command packet is received, an attacker could exploit the timing window between these tasks to potentially manipulate radio protocol behavior in affected Snapdragon chipsets.
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 dataall versionsall versionsall versionsall versionsall versionsall versionsall versionsall versionsCVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 the device chipset modelRetrieve the Qualcomm Snapdragon chipset identifier from the device system information, bootloader, or baseband firmware details. Common methods: check /proc/cpuinfo on Linux-based embedded systems, review device documentation, or query baseband version via AT commands (if supported).Affected if The chipset model matches one of the following: Apq8009w, Apq8017, Apq8096au, Aqt1000, Csrb31024, Fsm10055, Fsm10056, or Mdm8207
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Confirm firmware versionQuery the baseband or radio firmware version through vendor-specific interfaces (e.g., AT+CGMR for cellular modules, or inspect firmware image metadata if accessible). Document the exact firmware revision string.Affected if Any firmware version is present on an affected chipset listed in step 1, as the advisory states all versions are vulnerable
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Verify RRC/PDCP protocol stack is activeConfirm the device operates as a cellular radio endpoint using LTE/5G PDCP and RRC layers. This is typically inherent to any device with cellular modem functionality. If possible, inspect radio layer logs or network stack configuration for PDCP and RRC module activity.Affected if The device utilizes LTE or 5G radio protocols with active PDCP and RRC tasks (standard in any cellular-connected device with an affected chipset)
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Check for security patch levelReview the firmware changelog, vendor security advisories, or baseband patch information for any references to CVE-2021-30342 or Qualcomm security bulletins (typically released in December 2021 or later).Affected if No specific CVE-2021-30342 patch has been applied, meaning the race condition vulnerability remains unaddressed in the current firmware
A device is affected if it contains any of the listed Qualcomm Snapdragon chipset models (Apq8009w, Apq8017, Apq8096au, Aqt1000, Csrb31024, Fsm10055, Fsm10056, or Mdm8207) regardless of firmware version, since the vulnerability exists in the PDCP-RRC integrity validation timing window.
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.
From vendor dataApply Qualcomm-provided firmware/security patches for affected Snapdragon product lines; coordinate with device manufacturers for firmware updates.
- Consultation6.0 h
- Implementation16.0 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 $10,656.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30342 — 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-2021-30342 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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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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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