Malicious PDF — malware analysis report

Static analysis result for SHA-256 db5a915eb4001941…

MALICIOUS

PDF

104.6 KB Created: 2021-03-10 12:58:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 8649d8a4148871a07f4bd764931ea855 SHA-1: be91a8445fde8472628abd04a933862404b10922 SHA-256: db5a915eb400194183c5c9de74f5eee3d118678a91f53fb58d7a4e5b5796e093
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF document contains a large number of embedded links, many of which point to disposable hosting and redirect to malicious infrastructure. The primary malicious link identified is `https://yafferge.ru/strik?utm_term=how+to+remove+acne+spots+at+home`, which is presented as a lure for information on acne removal. The document's structure and link farm behavior strongly suggest it is designed to drive traffic to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 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.
  • 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.
  • 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=how+to+remove+acne+spots+at+home In PDF document text
    • https://static.s123-cdn-static.com/uploads/4372371/normal_5feba5920ef10.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461525/normal_6042228721e18.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444869/normal_6046cb66ec4fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374843/normal_600c02e27ac43.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461245/normal_60338a19a96ce.pdfIn PDF document text
    • http://jegoxijiruvika.22web.org/lexical_semantic_theory.pdfIn PDF document text
    • http://genokoti.iblogger.org/14686511796.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454819/normal_5fe09c78a815f.pdfIn PDF document text
    • http://zapazereti.22web.org/true_caller_app_and_install.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426942/normal_5fc571962f88a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420927/normal_5fdb24082da16.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/1fc2fec7-80e8-4549-908d-0c7bd9c35ace/les_5_points_de_larchitecture_moderne_le_corbusier.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55ca87a2-4b58-4b63-8dbf-e2bdd17d4f3a/pevejekigilab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/253bd112-55cb-4c3c-a34e-8fc7c6aed2fb/kuvimumaru.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/03f157f2-c3f8-4a87-8707-9f124107dd9d/how_long_does_a_dyson_dc44_battery_last.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7acf8444-27e2-43ec-acb4-61ad8bc48504/how_to_tell_if_turntable_needle_is_worn.pdfIn PDF document text
    • https://ff743420-c5e2-4527-a456-70ddb2a1abd8.filesusr.com/ugd/5178f2_037547cc178346e38ae0f73c662fdb24.pdf?index=trueIn PDF document text
    • http://woloripovopakop.rf.gd/arunachalam_movie_video_songs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e3e1679-a447-4fc3-812e-e5f076045e31/somewhere_over_the_rainbow_cello_sheet_music_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8193966-aaea-46f3-b6e8-172881919c65/dinogerozis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ff98bab-3343-4a1c-a45f-c3263de51b12/39949293890.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ff7d615-4c99-4229-b91f-37e6ad620588/dosivubopix.pdfIn PDF document text
    • http://buxazub.epizy.com/nutanikamefunilufexuji.pdfIn PDF document text
    • https://df256b98-640c-444d-885a-8195c7360722.filesusr.com/ugd/40b9e6_ec5ee68a4a81442aaafcca47268db62d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c328a162-bc55-43f3-998b-ca3308134f15/dekekuginotozedezunuja.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_off00015b6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B6C 5252 bytes
SHA-256: 770f470b8c3e69a3b821c27132652c1656f89f09f726b6df6d29c95417f1f2aa
font_01_sfnt_off00016d31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D31 11664 bytes
SHA-256: 4c1788cad1b4faa4a22134c2363b9220d524e1981efcf8864ba22b760d283302