Malicious PDF — malware analysis report

Static analysis result for SHA-256 854542de6bd61001…

MALICIOUS

PDF

89.1 KB Created: 2021-05-22 14:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 56641efa96108f4b28cbc58c6cedb89a SHA-1: 215929a7ab235e1551b2e95f814ba749f20c8355 SHA-256: 854542de6bd6100184bc7f22dea3a8d9aa2bd63889f55308b7c9f30939f71d4f
262 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it's a malicious redirector and part of an SEO link farm, designed to trick users into clicking on deceptive download links. The primary redirector URL is associated with known malicious infrastructure, and the document body, though heavily obfuscated, contains text related to free downloads, reinforcing the phishing lure. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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://yafferge.ru/strik?utm_term=tink+bonnie+and+clyde+free+mp3+download+fakaza In PDF document text
    • https://xonasuxodu.weebly.com/uploads/1/3/2/6/132681295/bonamifatodazel.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402504/normal_601a080fbfec9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385614/normal_602e72c3ea0a3.pdfIn PDF document text
    • https://xitititoludazo.weebly.com/uploads/1/3/5/9/135987602/0ee6d41e245d953.pdfIn PDF document text
    • https://gusoberususot.weebly.com/uploads/1/3/1/4/131454899/dibuneguga.pdfIn PDF document text
    • https://tisolalaw.weebly.com/uploads/1/3/0/8/130814234/dizebe-moxokekuramef-zodunota.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/e8ecd055-79b4-4f2e-9946-8950ce4b9099/12749248120.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f6b2ff3-a177-498a-b53d-f7b888ecb211/best_sat_chemistry_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c370adde-1bc3-4b4c-afc1-f32766d6f3c7/strange_city_names_in_michigan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5fdfd262-7f76-48c7-b4f9-b26ae18c2448/46825272564.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6cbdf7f9-1fbe-476a-a255-a56ba32d8217/lejaxinipupe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/99aecb24-2d79-45ca-b548-8046df64657e/beats_powerbeats2_wireless_earphones.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0654adc3-e29a-471f-8ef1-e6ac916827b4/polaris_trail_boss_250_starter_motor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a50fb7a0-1ddc-4ee3-a4d4-079e9a4d7a82/22713654845.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f3cc8ec4-b676-4e33-8dd9-ecd015477cc1/download_lagu_twenty_one_pilots_stressed_out_lyrics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/159172ba-09d3-4107-a3d6-fa02d2d2dbe6/basic_sewing_patterns_for_beginners.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/200955e4-a389-418c-b6da-4fa68d30e8f9/64487675976.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/562fa79a-0fdf-48f5-971c-1f54f4b5ea9d/pafamimedodeladi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6dd05c9f-469c-44c6-a8a9-e94fa3408e92/how_do_you_say_yes_please_in_french.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49428581-4d2b-4042-a891-1cc5568f89c8/3532368323.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f1bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BD 5392 bytes
SHA-256: 889fd3edabcd42076bd9fa2934af1527ad9beecd939018eb0d8fe16c5b66c9f2
font_01_sfnt_off000103fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103FB 2268 bytes
SHA-256: 253c50839ac6626950ebb29913d4b50f84c7f91f95a3b3e9574581cbf972dee6
font_02_sfnt_off00010e5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E5A 15020 bytes
SHA-256: 96182562ac79d87d7d5643a551a557f2a110934e19a822b5fd235644062abb99
font_03_sfnt_off00014046.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14046 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
font_04_sfnt_off00014df9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DF9 1736 bytes
SHA-256: 1648accd5638f26481c437d0e436fdfb03edab78dab75f4e73239278c8cddc19