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Ccn LiteApplication

CVE-2018-6948

CRITICAL · 9.8 CVSS v3.0 Published 2018-02-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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 · unedited
In CCN-lite 2, the function ccnl_prefix_to_str_detailed can cause a buffer overflow, when writing a prefix to the buffer buf. The maximal size of the prefix is CCNL_MAX_PREFIX_SIZE; the buffer has the size CCNL_MAX_PREFIX_SIZE. However, when NFN is enabled, additional characters are written to the buffer (e.g., the "NFN" and "R2C" tags). Therefore, sending an NFN-R2C packet with a prefix of size CCNL_MAX_PREFIX_SIZE can cause an overflow of buf inside ccnl_prefix_to_str_detailed.

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 confidence

In CCN-lite 2, the ccnl_prefix_to_str_detailed function allocates a fixed-size buffer of CCNL_MAX_PREFIX_SIZE but does not account for additional characters written when NFN (Named Function Networking) is enabled. Specifically, NFN and R2C tags are appended to the buffer, causing an overflow when a packet with a maximum-size prefix is processed.

MitigationDisable the NFN (Named Function Networking) feature in CCN-lite 2 if not required, or apply the vendor patch to properly size the buffer or add bounds checking to prevent overflow when NFN tags are appended.

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
Ccn LiteApplication
Affected:= 2.0.0

CVSS 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:3.0/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify CCN-lite installation and version
    Run 'ccn-lite -v' or check the source code version.h/version.txt for the installed copy. Look for version 2.0.0 specifically.
    Affected if The installed version is CCN-lite 2.0.0
  2. Check if NFN support is compiled into the binary
    Run 'ccn-lite -h' to view compiled features, or inspect the build configuration/config files for NFN_ENABLE or similar compile-time flags. Search source files for '#define CCNL_SUITE_NFN' or 'WITH_NFN'.
    Affected if NFN (Named Function Networking) support is enabled in the build
  3. Verify the vulnerable function exists in the installation
    Search the source code for the function 'ccnl_prefix_to_str_detailed' to confirm the vulnerable code path is present. Check if CCNL_MAX_PREFIX_SIZE is defined.
    Affected if The ccnl_prefix_to_str_detailed function is present and uses a fixed CCNL_MAX_PREFIX_SIZE buffer without accounting for NFN tag length
  4. Check runtime configuration for NFN service activation
    Inspect running configuration or startup scripts for NFN service flags such as '--nfn' or 'nfn=1' that would cause NFN tags to be appended to prefixes at runtime.
    Affected if NFN service mode is actively enabled during CCN-lite operation

A user is affected if CCN-lite version 2.0.0 is installed with NFN support enabled (either at compile-time or runtime), allowing the fixed-size buffer overflow to occur when processing maximum-length prefixes with NFN tags appended.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Disable the NFN (Named Function Networking) feature in CCN-lite 2 if not required, or apply the vendor patch to properly size the buffer or add bounds checking to prevent overflow when NFN tags are appended.

Recommended fix Moderate confidence
  1. 1. Locate the function ccnl_prefix_to_str_detailed in the CCN-lite source code
  2. 2. Identify the buffer declaration with size CCNL_MAX_PREFIX_SIZE (typically a local char array or malloc'd buffer)
  3. 3. Increase the buffer size to CCNL_MAX_PREFIX_SIZE + additional space for NFN tags (e.g., +16 bytes to accommodate "NFN", "R2C", and separator characters)
  4. 4. Alternatively, add proper bounds checking before writing to the buffer: verify (prefix_length + nfn_tag_length) <= buffer_size before each strcpy/strcat call
  5. 5. If NFN is not required in your deployment, disable NFN compilation flag (typically NFN flag in Makefile) as a workaround to prevent the overflow
  6. 6. Recompile CCN-lite with the modified code
  7. 7. Test with an NFN-R2C packet containing a prefix of maximum size to verify the overflow is prevented
Caveat Increasing the buffer size has minimal risk; disabling NFN removes Network Function Networking capability if your application requires it

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Ccn Lite Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing5.0 h
  • Review / QA3.0 h
17.0 hours of engineering $2,970
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2018-6948 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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