Malicious PDF — malware analysis report

Static analysis result for SHA-256 ebf2328c235dcc54…

MALICIOUS

PDF

78.6 KB Created: 2021-04-08 07:13:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 74cdb458afed2151789d411b3a8d7f93 SHA-1: 7956a2925bda6fbed9663e86b8106e35863337ca SHA-256: ebf2328c235dcc54d54af70ab658d5a0cc5963d0e6c7058f1bd11af5e9e1a2ae
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_LINK_FARM' indicates the presence of a large number of external links, suggesting a link farm or phishing operation. The embedded URL 'https://jacksth.ru/strik?utm_term=operations+research+analyst+jobs+in+canada' further supports the phishing or SEO manipulation attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://jacksth.ru/strik?utm_term=operations+research+analyst+jobs+in+canada
    • https://gefozusep.weebly.com/uploads/1/3/5/3/135346228/mawimitefivu_rirife.pdf
    • https://puxorubawi.weebly.com/uploads/1/3/5/3/135349856/dd06db03.pdf
    • https://cdn-cms.f-static.net/uploads/4469828/normal_6011b6c27aaf2.pdf
    • https://kuvovoturuja.weebly.com/uploads/1/3/5/3/135322548/d8228c3ab864a4.pdf
    • https://deremufirig.weebly.com/uploads/1/3/4/8/134854029/9639035.pdf
    • https://static.s123-cdn-static.com/uploads/4371003/normal_6007efa298b1a.pdf
    • https://cdn-cms.f-static.net/uploads/4411696/normal_6031bb9240d96.pdf
    • https://static.s123-cdn-static.com/uploads/4416659/normal_5ff794a98aad2.pdf
    • https://gajebafanagifim.weebly.com/uploads/1/3/2/8/132815836/xozakuxilogozi-tarogotagokuxo-radasojibilup.pdf
    • https://cdn-cms.f-static.net/uploads/4377662/normal_602c5fddeef10.pdf
    • https://sovajavab.weebly.com/uploads/1/3/4/0/134041947/1825483.pdf
    • https://kupugaxome.weebly.com/uploads/1/3/0/9/130969415/6140dc.pdf
    • https://cdn-cms.f-static.net/uploads/4446030/normal_6049ab31009ed.pdf
    • https://cdn-cms.f-static.net/uploads/4427097/normal_6036f6091a7c8.pdf
    • https://visopitolunew.weebly.com/uploads/1/3/1/4/131483219/rijonu.pdf
    • https://cdn-cms.f-static.net/uploads/4475376/normal_602b5afb37e32.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c79d2463-2874-46e2-bb75-5384043143d9/gudujixudanifofidus.pdf
    • https://uploads.strikinglycdn.com/files/053415a3-1913-4a48-8b68-0558d8a0c51a/rikelerawipalasos.pdf
    • https://uploads.strikinglycdn.com/files/7add52c0-9eca-4f59-902e-754dc7a7ca39/nadivineb.pdf
    • https://s3.amazonaws.com/fixararololu/what_happens_at_the_end_of_outlander_book_5.pdf
    • https://uploads.strikinglycdn.com/files/866d0d76-7490-4ab3-9036-b7434f7827b8/ancient_greece_religion_and_culture.pdf
    • https://uploads.strikinglycdn.com/files/c6544f3b-83c5-48b4-8e29-28222982fc23/shark_navigator_vacuum_maintenance.pdf
    • https://s3.amazonaws.com/zupenafud/7726020700.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_off0000f4bc.bin
f75eeb861d3ad62edff8d711317849679a15dda69d72519ad76c0f56853f69d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BC 5504 bytes
font_01_sfnt_off00010767.bin
6b6a1ff02b6a5cb78b3a760f42796dacea0d7453324f1f7153f268e9a3b6deaa
pdf-font-stream PDF embedded font (sfnt) at offset 0x10767 10964 bytes