Malicious PDF — malware analysis report

Static analysis result for SHA-256 361b2521ef24aca2…

MALICIOUS

PDF

71.4 KB Created: 2020-12-07 03:57:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 195df3b415d6e8cee75d8b9bbba9fcd1 SHA-1: 45bd47bf2ba230c75ece62756f93eca495f7b406 SHA-256: 361b2521ef24aca2637587894a2cb534e3cf7b4ba9c16d98c73972cfddef27c2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://trafftec.ru/strik?utm_term=cleveland+high+school+reseda+california+alumni
    • https://gafalevomunu.weebly.com/uploads/1/3/4/2/134235362/727948.pdf
    • https://namukizup.weebly.com/uploads/1/3/4/7/134748015/ruwifemokexareg.pdf
    • https://lotagixowila.weebly.com/uploads/1/3/1/1/131164100/0bced5e92f7688.pdf
    • https://xodasolilixodi.weebly.com/uploads/1/3/4/8/134874129/4521058.pdf
    • https://kiseridebajesa.weebly.com/uploads/1/3/1/4/131408791/fowavawimop-jubozaxudukoxu.pdf
    • https://dutajidadu.weebly.com/uploads/1/3/4/7/134730474/c62ab695cfd.pdf
    • https://burubigek.weebly.com/uploads/1/3/4/8/134884838/zorezoso_sijiparimot_takipi_wiwokisijitika.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/afca56f4-3ee4-4d81-bd07-3d8969410cc7/21512543961.pdf
    • https://s3.amazonaws.com/subud/allah_ke_99_naam_download.pdf
    • https://static1.squarespace.com/static/5fc2de36a5bc066edfb2733d/t/5fc3e4293485235c863e2447/1606673450486/34766053406.pdf
    • https://static1.squarespace.com/static/5fc50ab95687f52b6b9bd685/t/5fca1bc2fedaa13a4869fa13/1607080898291/diy_halloween_party_ideas_for_adults.pdf
    • https://static1.squarespace.com/static/5fc66fe517e72026400ff170/t/5fcc0b77cded405bb8c56535/1607207799412/vukupokilubiwos.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cdd5.bin
b1a9ff6ba35dc6afe0897100fc92f3f1f3234f8fbf85b49142f1f5db2d57e62f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDD5 2940 bytes
font_01_sfnt_off0000d861.bin
01014a6a97e1259fe2a659abdefeab753a4e4cbfbbe13ef88c3c54e1800688e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD861 5400 bytes
font_02_sfnt_off0000ea99.bin
6a850c2431f48699225933d85b4b45035e49e2c69004780bb8cc6fb1439fe6a1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA99 10556 bytes