Malicious PDF — malware analysis report

Static analysis result for SHA-256 d57d4761876c48cf…

MALICIOUS

PDF

79.7 KB Created: 2021-06-17 10:28:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 4ac2cfc907e13fa1f88aa9233ee11f2b SHA-1: 3919713ae00ad356bbe12a12cfb7f459569d5598 SHA-256: d57d4761876c48cf3fdceba804a71c866b76025ca9b5c64ca82aeba34c7ff07a
176 Risk Score

Malware Insights

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

This PDF file exhibits characteristics of a malicious document, including malformed streams and a high ML classifier score. It contains numerous links to compromised websites and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body, though obfuscated, appears to be a lure related to search results, likely intended to facilitate the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://pistant.ru/uplcv?utm_term=christmas+carol+fall+on+your+knees+lyrics PDF link annotation
    • http://am-assets.com/aom/magnolia/userfiles/file/4976904662.pdfIn PDF document text
    • https://agatanorek.com/files/file/60163409824.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/3642230250.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609da4cc571d6---45429731743.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/77m9bfbs0vlrlh6vvdiuclecn3/manojaxeri.pdfIn PDF document text
    • https://www.epicbrands.co/wp-content/plugins/super-forms/uploads/php/files/ab250216ec2aa2df1590117b4a94edeb/jakabafowumuwebebamutu.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d040ef4038---bexiluloxazofeluwapebis.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/983f901aa88b8b5f097dd4f17f342727/bifitotevikotifo.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/d8d9208e254528b8243dc73b86769414/26896685769.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c78062bf1d5---rozarebo.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ab83460d8ed---mixefaxo.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16086668c60609---xujokoxiganodaresezor.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160b5aa0913966---61660039604.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/82280734915.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/kokufubenoj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000f999.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF999 5192 bytes
SHA-256: 3d42e3a4ad60c85600f258f20d0f2f5a592f297a22083dd285c1dc56209beeed
font_01_sfnt_off00010b18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B18 12000 bytes
SHA-256: d8ce968ef3bfa0895ed79bf52cf17e1e9d5f2cc618e6d7f4e2dbb5eca984333f