Malicious PDF — malware analysis report

Static analysis result for SHA-256 164e20ad86ab55c7…

MALICIOUS

PDF

77.5 KB Created: 2021-03-28 18:23:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: f077bdddb16dee1c1c8d30ea7bf6e0e3 SHA-1: bf4adb2d90b18143c84c68acba68e24a63dcf62d SHA-256: 164e20ad86ab55c7f5728eb0c47d4ca5c968b55724892c7ea3a69eeed1ffdfbf
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as Pdf.Phishing.Trojan. The document body, though heavily obfuscated, contains metadata related to 'wkhtmltopdf' and a 'service manual' lure, reinforcing the phishing pretext. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ponafet.ru/strik?utm_term=kenmore+90+series+dryer+service+manual PDF link annotation
    • https://rigukolanerimi.weebly.com/uploads/1/3/4/5/134519373/3337267.pdfIn PDF document text
    • http://bepedegikojafeb.22web.org/zipimekegujugejal.pdfIn PDF document text
    • https://nidexopike.weebly.com/uploads/1/3/1/4/131407316/jebajafuxutubejeku.pdfIn PDF document text
    • https://cdn.sqhk.co/zanivuwiduvo/yZRheDl/the_trail_carry.pdfIn PDF document text
    • https://cdn.sqhk.co/rugofufol/Hjbqhjn/commuters_sans_font_download.pdfIn PDF document text
    • http://fawatakixur.iblogger.org/depisanawesofa.pdfIn PDF document text
    • https://cdn.sqhk.co/gobajejuz/ieijTgg/90865051511.pdfIn PDF document text
    • https://metesanej.weebly.com/uploads/1/3/1/8/131858044/ledak.pdfIn PDF document text
    • https://cdn.sqhk.co/runusamopit/jfjOjax/88960027518.pdfIn PDF document text
    • http://dapovevi.mywebcommunity.org/14778522220.pdfIn PDF document text
    • http://vaxenovutejuzid.sportsontheweb.net/boulevard_of_broken_dreams_drum_tab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4095172d-bd2f-4181-91d7-dd424e653400.filesusr.com/ugd/df73ab_69818186a2bc4c20971c4cd1a1b07b5b.pdf?index=trueIn PDF document text
    • https://0c1adbbe-b65a-4c28-9da2-87cea21e0636.filesusr.com/ugd/496951_9011f862c109426ab8296f1ba12e2793.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/145b3769-0b52-4f5e-93c3-c5d14c0c1be1/como_crear_un_archivo_zip_en_windows_7.pdfIn PDF document text
    • https://c2093f15-f4fb-4bda-9582-db5404103fa6.filesusr.com/ugd/b28561_f2f101fc468b42b48d33e0de67cfdbae.pdf?index=trueIn PDF document text
    • https://4a1cfc67-5981-466d-a13b-75576fe7431f.filesusr.com/ugd/64e449_70f744f012354115af03db66a8a29a4d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2621906e-0337-46eb-a715-d47738283079/foxedosopororewetikeri.pdfIn PDF document text
    • http://laganomezavarof.epizy.com/taputirisanigilufed.pdfIn PDF document text
    • http://bejanifezilo.atwebpages.com/40027090399.pdfIn PDF document text
    • http://rorevofiw.epizy.com/21866086168.pdfIn PDF document text
    • http://kifilexaxinazer.epizy.com/kenmore_washer_wont_spin_on_spin_cycle.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE49 5512 bytes
SHA-256: 8f4ac3cc72ebb10eb5b20f7831d429706520b49df788c5427dfede84b382c840
font_01_sfnt_off000100f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F8 11500 bytes
SHA-256: 1e30b29a0fd681442b85e4cd03b01d02196fb3d60370a0b99977355de8e74642