Malicious PDF — malware analysis report

Static analysis result for SHA-256 f39aef7504aa43cf…

MALICIOUS

PDF

78.0 KB Created: 2021-03-06 23:39:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: e1fcc51cf34b514b59cd41350a5d13a4 SHA-1: f6b8de1464f02ff21c67554fc5f34fea38e89bb5 SHA-256: f39aef7504aa43cf9df903956a61d3f46a9822f9bb4574671f0efaecd64c1bb7
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting services, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for distributing malware or conducting phishing. The document body, though garbled, contains keywords related to a snowblower sale, serving as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://baarspo.ru/strik?utm_term=ariens+724+snowblower+for+sale PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4501204/normal_6006b044b2d24.pdfIn PDF document text
    • http://tunezazetadu.22web.org/chakravyuha_yenaithu_video_song.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380395/normal_601dc8fa03b42.pdfIn PDF document text
    • http://dutalamujuso.66ghz.com/your_lie_in_april_clarinet_sheet_music.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487191/normal_60367007c01b4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413223/normal_5ffac3a94e0c9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424347/normal_5ff210579b834.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0f7a2101-273c-4f7f-b1fd-079d1ad923c1.filesusr.com/ugd/a7ea6f_31d4f5c2ffb449aea7c07a88f0298e9e.pdf?index=trueIn PDF document text
    • https://4ef57e19-9a2e-4e6f-a444-f6b59f982a39.filesusr.com/ugd/4c1554_e10bdafa68d94b379d8d9b8c85d54c44.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/38fafa30-6418-4aa4-9ec4-9f1b90f152de/23570612307.pdfIn PDF document text
    • https://73a1781f-5c9f-4c76-8a11-a8e8c44f336a.filesusr.com/ugd/d9f7b5_982752b76a03403c9e7981fd0b9f7b71.pdf?index=trueIn PDF document text
    • https://71a5d838-4e22-4830-8da1-7955ec3365f5.filesusr.com/ugd/f2f43e_1799c73d6bfa4c2d896b9427f1a8dcbc.pdf?index=trueIn PDF document text
    • http://fikexole.rf.gd/compare_data_in_excel_sheets_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd0ec3eb-70c7-4028-aa6b-e2b80cf15928/nisenefofapifugopuso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e91bfbd-f7fb-48cd-ab3a-b5355324fe7c/singer_touch_and_sew_special_zig_zag_model_756.pdfIn PDF document text
    • https://13cfbe10-32e4-4d7a-9072-8dbd3280e6b8.filesusr.com/ugd/994e9e_a1959803878c4b3eb80a6e6f57f2b5e9.pdf?index=trueIn PDF document text
    • http://noxudabewoxedit.rf.gd/finiwago.pdfIn PDF document text
    • https://8c56b32b-3398-45d6-9c0b-b55146621f16.filesusr.com/ugd/6924eb_ca4c44a39c4f4718a4397d68f766c6ad.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/abab41be-0b23-45cc-baa2-a3bee2ffd36f/yamaha_stagepas_600i_mixer_stand.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/732d123f-e643-4361-b092-e54ca6bcbc61/orhan_pamuk_best_sellers.pdfIn PDF document text
    • https://b724dda4-e2e0-47c5-811c-ae3b7273578b.filesusr.com/ugd/a1e5ee_5edc7263e75f4eb0858e1c96405d0717.pdf?index=trueIn 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_off0000f282.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF282 5284 bytes
SHA-256: d0e61f9e92b9fcd653d58955c5ef9af36ec564c8bd89d1621285b97d7728d817
font_01_sfnt_off000104aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AA 10636 bytes
SHA-256: 2d48cb52284a7768ef75a8c1e79cecdc45d349f0f8e22678f70e070b647dbd15