Malicious PDF — malware analysis report

Static analysis result for SHA-256 13ea40cfe5b240d8…

MALICIOUS

PDF

77.8 KB Created: 2021-05-29 10:10:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e8d3bdc562ced877c1c737d837829f42 SHA-1: 9dca02701f93495c54aae5682c8d28f18b31750c SHA-256: 13ea40cfe5b240d87dc6a5a7e422946b06cc2a06f99710585416a8683448c729
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a critical heuristic identifying it as a link farm. One of the primary external URLs is golowaki.ru, which is likely used for malicious redirection. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://golowaki.ru/123?utm_term=footer+template+gridview
    • https://cdn-cms.f-static.net/uploads/4378157/normal_6029529b15c0c.pdf
    • https://cdn-cms.f-static.net/uploads/4476780/normal_603010b6657b3.pdf
    • https://cdn-cms.f-static.net/uploads/4500668/normal_5fd356ce27ad5.pdf
    • https://static.s123-cdn-static.com/uploads/4446395/normal_5fcd0c812b860.pdf
    • https://cdn-cms.f-static.net/uploads/4497697/normal_5fe70ab425cec.pdf
    • https://fezagexagowib.weebly.com/uploads/1/3/5/3/135313062/c06226788.pdf
    • https://cdn-cms.f-static.net/uploads/4375356/normal_5fd634d7503d1.pdf
    • https://tunivarururi.weebly.com/uploads/1/3/4/0/134041149/2126119.pdf
    • https://cdn-cms.f-static.net/uploads/4476590/normal_6064117755ec0.pdf
    • https://cdn-cms.f-static.net/uploads/4378161/normal_606037c0f35c2.pdf
    • https://cdn-cms.f-static.net/uploads/4451970/normal_6064b43b3a0b0.pdf
    • https://cdn-cms.f-static.net/uploads/4460446/normal_600d4fdec8fed.pdf
    • https://jevuzukolusiwu.weebly.com/uploads/1/3/0/7/130739503/desififoposerugu.pdf
    • https://cdn-cms.f-static.net/uploads/4384154/normal_60635c17c5506.pdf
    • https://cdn-cms.f-static.net/uploads/4446492/normal_604fb2cc067a3.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/8005d4ff-dba6-479a-a5b3-2ddb5ff118bf/how_to_show_bleed_marks_in.pdf
    • https://uploads.strikinglycdn.com/files/f8ae52bb-4428-49c0-a733-6460bfed4e88/84009435059.pdf
    • https://uploads.strikinglycdn.com/files/35e9e85a-e865-49d3-8a63-0b67db242f25/fodmap_list_of_foods.pdf
    • https://uploads.strikinglycdn.com/files/777e6aea-1762-4424-8f6d-2e2b475848bb/14945831704.pdf
    • https://uploads.strikinglycdn.com/files/84d30999-7649-48f9-95b4-c086a40fe844/learn_fluent_english_in_30_days.pdf
    • https://uploads.strikinglycdn.com/files/3d46bfb3-8eb7-40d0-852d-45f5509d20c1/husqvarna_455_rancher_service_kit.pdf
    • https://uploads.strikinglycdn.com/files/7300bf23-5143-4885-8f7b-ec58155811f4/periodic_table_new_elements_2016.pdf
    • https://uploads.strikinglycdn.com/files/f9fb7bdd-8929-4d9b-8cf4-4b0fddd96bf8/9192136958.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f113.bin
b018fa914022d3d4326ba87aa5d0cc041047c61452a5bd0e0f55a9f71f35dd1a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF113 5208 bytes
font_01_sfnt_off000102c6.bin
6b6a70cd9a9a1404c346a46005323abfb9c210750d4baeab93f0bc0bacff3699
pdf-font-stream PDF embedded font (sfnt) at offset 0x102C6 11500 bytes