The server in Dropbear before 2017.75 might allow post-authentication root remote code execution because of a double free in cleanup of TCP
The server in Dropbear before 2017.75 might allow post-authentication root remote code execution because of a double free in cleanup of TCP listeners when the -a option is enabled.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for help- Published
- May 19, 2017
- Updated
- Jun 16, 2026
- EPSS
- 5.7% · 93th percentile
- CWE
- CWE-415
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Report tools
Action score
37
Monitor
Low priority for now.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 2 / 30 · 5.7%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| dropbear ssh project | dropbear ssh | cpe:2.3:a:dropbear_ssh_project:dropbear_ssh |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| netapp | h410c firmware | cpe:2.3:o:netapp:h410c_firmware |
| netapp | h410c | cpe:2.3:h:netapp:h410c |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux8.0
- dropbear ssh project dropbear sshbefore 2017.75
- netapp h410c firmwareall versions
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.4 | dropbear | before 2017.75-r0 | 2017.75-r0 |
| Debian:12 | dropbear | before 2016.74-5 | 2016.74-5 |
| Debian:8 | dropbear | before 2014.65-1+deb8u2 | 2014.65-1+deb8u2 |
Same product
dropbear ssh project: all recordsOther highest-scoring records for the same primary product.
- CVE-2016-7406Format string vulnerability in Dropbear SSH before 2016.74 allows remote attackers to execute arbitrary code via format string specifiers in42Plan
- CVE-2016-7407The dropbearconvert command in Dropbear SSH before 2016.74 allows attackers to execute arbitrary code via a crafted OpenSSH key file.41Plan
- CVE-2016-7408The dbclient in Dropbear SSH before 2016.74 allows remote attackers to execute arbitrary code via a crafted (1) -m or (2) -c argument.36Monitor
- CVE-2020-36254scp.c in Dropbear before 2020.79 mishandles the filename of .33Monitor
- CVE-2016-3116CRLF injection vulnerability in Dropbear SSH before 2016.72 allows remote authenticated users to bypass intended shell-command restrictions 31Monitor
- CVE-2007-1099dbclient in Dropbear SSH client before 0.49 does not sufficiently warn the user when it detects a hostkey mismatch, which might allow remote31Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| alpine:dropbear | 2017.75-r0 · Alpine:v3.4 | Package registry (OSV) |
| debian:dropbear | 2016.74-5 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-415 · Double FreeCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2017q2/001985.html
- www.debian.org/security/2017/dsa-3859
- security.netapp.com/advisory/ntap-20191004-0006/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.