Malicious PDF — malware analysis report

Static analysis result for SHA-256 f76f03f16b3ea30d…

MALICIOUS

PDF

85.7 KB Created: 2021-05-30 14:51:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 4c7e5f8c4ef42adaa8b7066656f7675a SHA-1: 86fc9e0d01fc7cc19d433284f33c21741f1f8fd5 SHA-256: f76f03f16b3ea30da7161d755d9f6c4418aacda886d82830e994d01323a710b6
204 Risk Score

Malware Insights

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

The PDF file contains multiple heuristics indicating it is a phishing lure, including PDF_SEO_LINK_FARM and PDF_SEO_UTM_REDIRECTOR_LINK. It directs users to a URL that appears to be an SEO redirector, likely to download a malicious payload. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://midufefew.ru/strik?utm_term=english+speaking+activities+b1+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4492574/normal_60049967c1697.pdfIn PDF document text
    • https://popoxalisasuper.weebly.com/uploads/1/3/0/7/130775362/babezuzarewuva_lewefabuwusat.pdfIn PDF document text
    • https://jizejazubaro.weebly.com/uploads/1/3/4/3/134373429/zuvinanim.pdfIn PDF document text
    • https://funovupudejo.weebly.com/uploads/1/3/4/4/134473131/gepamadorobefemenid.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481154/normal_60621814d571b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374207/normal_604635c30f1b9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387819/normal_605ab88f544fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467273/normal_6065ebda16ecc.pdfIn PDF document text
    • https://toguxiwo.weebly.com/uploads/1/3/4/6/134645105/64718ceed3efe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/94158f94-0ab4-41ad-b374-18ff807f3370/mawif.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26f5ffa2-9a42-435e-9006-9a867d1743e3/fevigukazogutakidosukuk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/280a1259-cf22-4e53-9b7d-3a2f39d2bd37/ariens_snowblower_624e_engine_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd9d09da-b77c-4e16-bfc7-559ed5fcfe10/35132029993.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fcc7dbce-40db-4b32-a06f-2b832755e4e1/how_to_start_nixon_watch.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ebd34e2-5053-460d-901d-8207569a1299/1.6_02.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/304d128a-e2d3-4336-82a0-21d70b30117f/how_to_improve_your_bad_handwriting.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/360bd49e-42ab-4ba8-8bed-53e39cd7a8dd/mfj-939i_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/69bc614c-7e92-4c78-bffc-4572cc6b3c5c/xaluxun.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_off00010b35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B35 5592 bytes
SHA-256: 6774cfdc445e0fc916c2b0e3c6d1644b7de5a35cf6d4ae7bee08771d15d56520
font_01_sfnt_off00011e4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4B 13336 bytes
SHA-256: a3549d647248bd17edf9e81d4be2b713b8dea1c89264cfd57e9b5913a906cc83