Malicious PDF — malware analysis report

Static analysis result for SHA-256 1710ee68af96b1a7…

MALICIOUS

PDF

83.1 KB Created: 2021-05-26 14:57:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 7ec9758159c26b407b9bda6285d579eb SHA-1: 258e1ad8481519f57db0113775c8665ad90d1853 SHA-256: 1710ee68af96b1a72094ffe6f9692352e3c04648e07d7a83931133347182080f
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external links, many of which point to SEO redirectors and link farms, a common tactic for phishing or malware distribution. One prominent URL, 'https://leonvi.ru/strik?utm_term=how+to+qualify+for+autism+service+dog', appears to be part of a lure to trick users into clicking, potentially leading to a malicious site or download. The presence of PDF_SEO_LINK_FARM and PDF_SEO_UTM_REDIRECTOR_LINK heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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://leonvi.ru/strik?utm_term=how+to+qualify+for+autism+service+dog PDF link annotation
    • https://taxefijiduru.weebly.com/uploads/1/3/5/3/135311915/vigudaxidawumize.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408704/normal_60679db4406cf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367667/normal_60421f2bd2870.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403119/normal_60162b80eb0f9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495525/normal_605b8d867e202.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481527/normal_60321348aed9b.pdfIn PDF document text
    • https://lusimijibujadex.weebly.com/uploads/1/3/4/6/134677052/f6c61813d2b63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446377/normal_6041c23487fbd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393637/normal_5feb5618d122a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4470553/normal_5ff00f2865e08.pdfIn PDF document text
    • https://rovorakule.weebly.com/uploads/1/3/4/7/134774255/73f0bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456666/normal_600ff6bbca1be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371523/normal_5fd676aa3a05b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4406806/normal_600822c2ae537.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402294/normal_605886bfe6880.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459631/normal_5ff0234116ce5.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/db172de6-cd4d-4daf-9b39-7c40538b4ed7/4489842294.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/daf51fd2-ad90-4bef-8eac-eb7fc74a4707/maze_runner_death_cure_movie_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e3e0d4e-8baf-49b6-b0d0-4406064acd5b/xifenatipekeju.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce97efd9-d374-49db-9523-a8c80b65f86f/44895649366.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ce85524-6341-4447-bbee-46cb4ad47e60/galaxy_s9_plus_charger_walmart.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1e6fb61c-aa37-4cde-b7b2-d03e2200ea08/3625049827.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_off00010445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10445 5680 bytes
SHA-256: 5c11201fdfccee4fdeb209537d8a6f02f21da36b74a998d77752bf7ab895ea59
font_01_sfnt_off000117a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117A0 11480 bytes
SHA-256: e03c65be78383d8666292a73d9ce06e14929018e23386ae1e3f0a30a1843cef6