Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f132706fd183328…

MALICIOUS

PDF

83.0 KB Created: 2021-04-08 04:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 3e50cac8cdf0ef8b27c46733eb47ef2b SHA-1: d7c66083eab4da2811028b076491ca0452b95803 SHA-256: 3f132706fd183328b5855ecd027e210408e441357abec55a90f3640f41dcbb2c
186 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to redirect users. One of the primary URLs extracted is 'https://maypoin.ru/strik?utm_term=can+i+use+synthetic+oil+in+my+snow+blower', which is likely part of a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://maypoin.ru/strik?utm_term=can+i+use+synthetic+oil+in+my+snow+blower PDF link annotation
    • https://marikikugawu.weebly.com/uploads/1/3/5/3/135326377/c72eb72.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417408/normal_6052b6be099f4.pdfIn PDF document text
    • https://bevarepovorumi.weebly.com/uploads/1/3/2/3/132303359/26a80d8ec18f4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449968/normal_5fc5ebf09e0f4.pdfIn PDF document text
    • https://xizuzesujebowu.weebly.com/uploads/1/3/4/6/134666185/c4c91095.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447646/normal_601cd3f38232a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460463/normal_6041e063952da.pdfIn PDF document text
    • https://kitopelok.weebly.com/uploads/1/3/4/3/134355781/d2e435c1c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485927/normal_6039a358e9b8a.pdfIn PDF document text
    • http://sopidemeleket.mygamesonline.org/71217104160.pdfIn PDF document text
    • https://fusofopafufet.weebly.com/uploads/1/3/5/2/135294951/gotupegoguso.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379230/normal_605917ae8ff76.pdfIn PDF document text
    • https://tovuwofox.weebly.com/uploads/1/3/4/7/134731163/f85e64.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411915/normal_602daa7f31761.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/lukepepe/96608827059.pdfIn PDF document text
    • https://s3.amazonaws.com/jajuzasalikirut/35959557920.pdfIn PDF document text
    • https://s3.amazonaws.com/febopa/oxford_picture_dictionary_third_edition_monolingual_dictionary.pdfIn PDF document text
    • https://s3.amazonaws.com/rodigapigeta/toyota_camry_se_for_sale_2014.pdfIn PDF document text
    • https://s3.amazonaws.com/lusabifef/vapijejasuwuwijogaxawexo.pdfIn PDF document text
    • http://pejemevogoge.myartsonline.com/rokixonenutitusekositi.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_off000107b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107B7 5276 bytes
SHA-256: b731045fef1521e7aa5f65429d21fff3a51b52e6ac5758a7b97286b694e30a5a
font_01_sfnt_off00011991.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11991 11008 bytes
SHA-256: 8f6f9a9799befcca78772ab51e252c4c17f1888cd1050edfa5caf7b39f3cfc96