Malicious PDF — malware analysis report

Static analysis result for SHA-256 81dabd4a3239545a…

MALICIOUS

PDF

71.8 KB Created: 2021-02-22 04:05:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 0397458551bd3c6483cfb1d1a54c0b4f SHA-1: 24e06cdea0093f5368d6c1d146ed89702a1ad059 SHA-256: 81dabd4a3239545abddf906cd9260f944bf81770bcbf62347fddd4ac166413b4
126 Risk Score

Malware Insights

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

The PDF file contains multiple embedded URLs, with one prominently featured in the document body, masquerading as a search result. This URL, https://seumenha.ru/wb?keyword=which%20robot%20vacuum%20cleaner%20is%20best%20for%20pet%20hair, likely leads to a phishing or malware distribution site. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and ClamAV detection further indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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://seumenha.ru/wb?keyword=which%20robot%20vacuum%20cleaner%20is%20best%20for%20pet%20hair PDF link annotation
    • https://zuxadozi.weebly.com/uploads/1/3/4/6/134662888/659362.pdfIn PDF document text
    • http://qwertyujg.xyz/705260278968jue3.pdfIn PDF document text
    • http://pesale.pro/boomerang_apk_latestylyya.pdfIn PDF document text
    • http://garant-ritual.online/weebly_for_teachersipy45.pdfIn PDF document text
    • http://giocodigital.fun/math_multiplication_worksheet_for_grade_3hfrhb.pdfIn PDF document text
    • http://mists.space/timolol_davis_drug_guidemxfri.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://nekofixas.rf.gd/dufelapofumowogemajowibe.pdfIn PDF document text
    • http://julajibumomas.rf.gd/13160744362.pdfIn PDF document text
    • http://loxeputogojew.rf.gd/gadejikaxutubupo.pdfIn PDF document text
    • http://tejutavufoxif.epizy.com/brochure_format_online.pdfIn PDF document text
    • http://figofubinodafe.rf.gd/wewatenejidojonilaxix.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF58 5352 bytes
SHA-256: 80097e4a26ff40d45801c2b68214ebe7b709a2dff89fbc28125eacc32691a476
font_01_sfnt_off0000e16a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16A 10248 bytes
SHA-256: d3b07ae4fb2c01ec562ce3d856e794a2b6fb7f05f50da8fd7d5e7d5a7b004a67
font_02_sfnt_off0001047e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1047E 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71