CVE-2016-5827
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 · uneditedThe icaltime_from_string function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (out-of-bounds heap read) via a crafted string to the icalparser_parse_string function.
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 heap-based out-of-bounds read vulnerability exists in libical versions 0.47 and 1.0. The icaltime_from_string function does not properly validate input when parsing a crafted string through icalparser_parse_string, allowing an attacker to trigger an out-of-bounds heap read leading to denial of service.
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= 0.47= 1.0.0CVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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.
-
Identify if libical library is installedRun 'pkg-config --modversion libical' or check your package manager for installed libical packages (dpkg -l | grep libical, rpm -qa | grep libical)Affected if libical is not installed or the package is not found - you are not affected; if installed, continue to version check
-
Determine the installed libical versionRun 'pkg-config --modversion libical' or check the output from your package manager command above; also check for libical.so in /usr/lib/ and run 'strings /usr/lib/libical.so | grep -i version' if neededAffected if Version is 0.47 or 1.0.0 - you are directly affected by this CVE
-
Verify if applications link against the vulnerable libical libraryRun 'ldd /path/to/your/application | grep libical' for any binaries or services that use libical, or check application dependenciesAffected if Any application dynamically links to libical version 0.47 or 1.0.0 - the vulnerability is present in your runtime environment
-
Check if icalparser_parse_string processes external inputReview application source code or configuration for calls to icalparser_parse_string with data from untrusted sources (user input, network, files from external parties)Affected if Your application calls icalparser_parse_string with untrusted iCal strings - the vulnerable code path is reachable and could be exploited
You are affected if libical version 0.47 or 1.0.0 is installed AND any application uses icalparser_parse_string to process external or untrusted iCal data, allowing a crafted string to trigger the out-of-bounds heap read in icaltime_from_string.
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 dataUpgrade libical to the latest version to obtain the security patch. If immediate patching is not possible, sanitize and validate all iCal input strings before passing them to icalparser_parse_string.
- Consultation2.0 h
- Implementation4.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,328.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-5827 — 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-2016-5827 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
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
- No spam, self-promotion, credentials, or personal data