Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c08c6b360dbded7…

MALICIOUS

PDF

94.2 KB Created: 2020-11-16 16:54:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 68c1c509ddf95756794a42de22a57182 SHA-1: 9d75cc56a438cd5fdd0ed19a5b31f2aeceb93de7 SHA-256: 4c08c6b360dbded7319f8e42a53eb22638267b802bafb383cf8fffc58387689c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, identified as a 'PDF_SEO_LINK_FARM' heuristic, suggesting a malicious intent to redirect users to potentially harmful websites. ClamAV and an ML classifier also flagged this PDF as malicious, specifically as a phishing trojan. The primary IOC is the initial URL that likely serves as the entry point to this link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://trafffe.ru/aws?utm_term=super+boot+manager
    • https://cdn-cms.f-static.net/uploads/4375896/normal_5f8ef74f7092a.pdf
    • https://cdn-cms.f-static.net/uploads/4380540/normal_5fa14260ddf6f.pdf
    • https://dojeviwenos.weebly.com/uploads/1/3/4/4/134491393/getewifidedabad.pdf
    • https://gatixitawenubik.weebly.com/uploads/1/3/4/6/134643062/tozidawo.pdf
    • https://cdn-cms.f-static.net/uploads/4391331/normal_5f9257e32aafa.pdf
    • https://cdn-cms.f-static.net/uploads/4405206/normal_5fad7cf9e9857.pdf
    • https://cdn-cms.f-static.net/uploads/4447434/normal_5fa07b09e5abe.pdf
    • https://cdn-cms.f-static.net/uploads/4447251/normal_5fa1198acd33d.pdf
    • https://cdn-cms.f-static.net/uploads/4454681/normal_5fafd6f22a2a3.pdf
    • https://naxesitigas.weebly.com/uploads/1/3/0/7/130740165/sisuderefasi_saviz_zebunil_ferenopiriko.pdf
    • https://tipefejiri.weebly.com/uploads/1/3/0/9/130969755/vepinifupunavir.pdf
    • https://jatuvukaxakepu.weebly.com/uploads/1/3/4/3/134313635/aa3855.pdf
    • https://cdn-cms.f-static.net/uploads/4446158/normal_5fa2ddb39b94a.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013569.bin
cdf862e26f24072aafe982ca283a3b2c441db539930de0c0de25c452636fd3b1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13569 5172 bytes
font_01_sfnt_off000146e6.bin
625c5c663e273ff41b01d8dcd4a7990a96487f17c7cfe7f4b114ff3b8e2359af
pdf-font-stream PDF embedded font (sfnt) at offset 0x146E6 11212 bytes