MEDIUM
CVE-2021-27839
CWE-1236Published: March 3, 2021· Updated: Jun 17, 2026
4.4
CVSS v3.1
Official Description
A CSV injection vulnerability found in Online Invoicing System (OIS) 4.3 and below can be exploited by users to perform malicious actions such as redirecting admins to unknown or harmful websites, or disclosing other clients' details that the user did not have access to.
Technical Analysis
CVE-2021-27839 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeUnchanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Affected Vendors & Products
bigprof1 product(s)
online invoicing system
Source: NVD CPE · 1 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (4)
→
https://github.com/bigprof-software/online-invoicing-system/releases/tag/4.4Release Notes · Third Party Advisory
→
https://www.jinsonvarghese.com/csv-injection-in-online-invoicing-system/Third Party Advisory
→
https://github.com/bigprof-software/online-invoicing-system/releases/tag/4.4Release Notes · Third Party Advisory
→
https://www.jinsonvarghese.com/csv-injection-in-online-invoicing-system/Third Party Advisory
Quick Facts
CVE IDCVE-2021-27839
CVSS Score4.4 / 10
SeverityMEDIUM
WeaknessCWE-1236
CISA KEVNo
Affected1 vendor(s)
PublishedMar 3, 2021
Related CVEs (CWE-1236)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-27839 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.