Malicious PDF — malware analysis report

Static analysis result for SHA-256 97d61eb6e4501bcf…

MALICIOUS

PDF

88.1 KB Created: 2021-09-20 18:13:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 35e661e3af4dc69736d64d0215b4d694 SHA-1: c1c4f4e19cee4bcb6d9155207e3a09f074233aca SHA-256: 97d61eb6e4501bcfaa1f7ac20519b266da07e936f0752666ec31b5c743cb3cc6
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and the ML classifier also indicated maliciousness. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates this pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://crysiq.ru/uplcv?utm_term=live+wallpaper+for+mobile+download PDF link annotation
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/68635903724.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/rodugol.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/xevaxus.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/81497966286.pdfIn PDF document text
    • http://kxzyjy.com/CKEdit/upload/files/31685178092.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/6534326779.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/48597251005.pdfIn PDF document text
    • https://pima-alarms.net/slicice/file/19644301323.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/fanikufemarerixivaxo.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/57915250738.pdfIn PDF document text
    • http://johnmichaelharrisonlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fisugogobud.pdfIn PDF document text
    • http://an-professional.ru/img/files/file/94935129080.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/juxezipifituwitizodibo.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/70427650176.pdfIn PDF document text
    • http://casaperugia.fr/userfiles/file/81310208657.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/vunalulaken.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130bf4cec665---kilogutanoburisopodik.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/62446885900.pdfIn PDF document text
    • https://gaadalagi.com/contents/files/68278476144.pdfIn PDF document text
    • http://linza-market.ru/upload/files/25839936854.pdfIn PDF document text
    • http://www.depomatrial.com/file/jadidi.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/e6a9df88521933b981e02d706694c62e/sikipexuludebul.pdfIn PDF document text
    • https://biroestarsa.hu/uploads/file/3358837552.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/fuxofonisukipo.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/cl7pcs2altdgbgas6mr4ll0h9n/devanonumadoruz.pdfIn PDF document text
    • https://thediamangroup.com/_images/files/31972100298.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A6C 18500 bytes
SHA-256: 9f6e68b64de54966422de45ba9ac496ef8e361f5f81d099577036151f4a52b7c
font_02_sfnt_off00013a6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A6B 10640 bytes
SHA-256: a42f10bc6f1c04f8f7df23b6aa47f3dd3d336a0973c98c5df402c83681c2533e