Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa60974fed6fd2d…

MALICIOUS

PDF

83.7 KB Created: 2021-06-25 16:54:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: bd1a69ce6d0d4bc2a1850d9577396513 SHA-1: f1221ae32cf6b04a1d28121df3dd2d191e62d8e8 SHA-256: efa60974fed6fd2da3f74f66ff9ea50c6ec56ade29eb5e61f34fbb7bd4de302d
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on compromised websites. The presence of multiple links to disposable hosting and the use of UTM parameters suggest a phishing or spam campaign aimed at driving traffic to malicious content. The document body is heavily obfuscated and unreadable, indicating it is not intended for human consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/af2a92e4iomjarus248u9gmgtf/rovawomedef.pdf In PDF document text
    • http://creatinglifeoptions.com/userfiles/files/77112543501.pdfIn PDF document text
    • http://gw73patriots.com/clients/1/1e/1ed986c9d410becccfd9995a8318e329/File/rikanukudutowabos.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/f996f4c2d095fd72a86d29977a9429d4/63824670308.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/2jco3k964klk0erkuuq2aargd6/19102978013.pdfIn PDF document text
    • http://innotack.com/userfiles/files/nizubusuwegagotijuvedisud.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/a0e6d997ea2ebb948ba5ddbba9cbd7de/39201104004.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/20212699275.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/babivavixikewabatu.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210510152008.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/so70lpba6l60kea2fb7r0mpfob/79690914884.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/vgip7j9vj8p36busvpuic82qf2/zadumolibisemadapagizolun.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099a24f0861f---jegolanatuzobosexaritabe.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/taniliwukuvutawenagipakew.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af2e6840469---wegomixozabawanejuta.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/8brkhg0e764i4oero4vu8fam0g/91930704284.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=straits+times+indexPDF link annotation
    • 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_off0000e231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE231 18348 bytes
SHA-256: 2158a7b87690663ef0c56917f5106265c59b7800b98025a1df533f9349238f8e
font_01_sfnt_off0001128a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1128A 10420 bytes
SHA-256: 485028956ae441d7c97a27de0bab5a7533b0d72a04b21081b377c08da1063366
font_02_sfnt_off00012a1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1