Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9c616d726f2c63d…

MALICIOUS

PDF

107.4 KB Created: 2021-03-21 10:09:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: f7df82ed55bcccf33aaaa56181806dee SHA-1: 12ce45b4a49fe99f71a51b0875c93cf0ab4fbb25 SHA-256: a9c616d726f2c63d55d99d20f290f577e93d5905a7b363ec603e76d464023c5e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 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://ponafet.ru/strik?utm_term=letter+from+birmingham+jail+commonlit+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4388613/normal_5fcd5126e6368.pdfIn PDF document text
    • http://jabudapitu.scienceontheweb.net/independent_auditor_s_report.pdfIn PDF document text
    • http://xofenejilomoz.iblogger.org/788146809.pdfIn PDF document text
    • http://navevukosuso.mypressonline.com/how_to_pair_photive_bluetooth_headphones.pdfIn PDF document text
    • http://kevebofuru.medianewsonline.com/what_is_sierpinskis_triangle.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380545/normal_6004a84ff2df0.pdfIn PDF document text
    • http://tusiteguluvora.getenjoyment.net/xolala.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4428083/normal_5ffb4f2aa3ca9.pdfIn PDF document text
    • http://tixaman.scienceontheweb.net/acer_aspire_one_722_laptop_price.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xumugipetoje.epizy.com/44503807733.pdfIn PDF document text
    • http://wugujub.onlinewebshop.net/tokyo_ghoul_re_call_to_exist_ps4_theme.pdfIn PDF document text
    • http://bosurigazo.epizy.com/rexovuvozakigenogabeg.pdfIn PDF document text
    • http://penanaras.myartsonline.com/the_myth_of_sisyphus_absurdism.pdfIn PDF document text
    • http://majuxitur.epizy.com/java_programming_with_examples.pdfIn PDF document text
    • https://s3.amazonaws.com/dorobukasawituw/90651622537.pdfIn PDF document text
    • http://gukupexokopiwug.epizy.com/ccleaner_ting_vit.pdfIn PDF document text
    • https://s3.amazonaws.com/gofilafixu/wirifilex.pdfIn PDF document text
    • http://xevorerokune.epizy.com/12610515959.pdfIn PDF document text
    • http://lipeporo.onlinewebshop.net/rational_numbers_as_decimals_worksheet.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000166dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x166DD 5544 bytes
SHA-256: 56049636c4a14773edb1ef44a8a321ab2768089a2ee491fc333cb3b8339983a4
font_01_sfnt_off000179ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x179AD 11256 bytes
SHA-256: 03cab0ac71553f7e8b960f53ef45ba2c09fc4c2cbecc15a7048dd1bd870c74c0