Malicious PDF — malware analysis report

Static analysis result for SHA-256 218e4a28cf82b1ae…

MALICIOUS

PDF

73.8 KB Created: 2021-03-31 14:32:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: a67ad1dbb498b9f9df7bf0f4a6ba4671 SHA-1: 189cc791f1433d74c820ee2d30cf411387b44d01 SHA-256: 218e4a28cf82b1aee559c15f3a15d1f3f35bc54ded6b45fdb78bfd893d01e8ba
186 Risk Score

Malware Insights

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

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 0.9991

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://resalured.ru/strik?utm_term=oxford+online+esl+placement+test PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4528876/normal_602456a23ffa1.pdfIn PDF document text
    • https://janodapos.weebly.com/uploads/1/3/1/6/131636969/zivefovonemebaw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391302/normal_6014a53d1fb08.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484814/normal_5feb08d1278e4.pdfIn PDF document text
    • http://nipugupaf.22web.org/fluke_177_true_rms_multimeter_price.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454819/normal_5fe09cb163e34.pdfIn PDF document text
    • https://ximizewilaxeju.weebly.com/uploads/1/3/1/3/131381769/gajebebakavar.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418184/normal_60301a8a7eca3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415534/normal_60307d33d3919.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387218/normal_60124f445e6d5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420230/normal_60530993148f8.pdfIn PDF document text
    • https://nutakiderovex.weebly.com/uploads/1/3/4/6/134622867/c317cf77232b.pdfIn PDF document text
    • https://palujaburufo.weebly.com/uploads/1/3/2/7/132740236/rulibalexexitav.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420597/normal_6000c0070ace4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://semazixiguf.rf.gd/70815680297.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0e47462c-2d9e-49d4-b860-1160e6c2e0a0/how_to_run_a_liquor_store_business.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5da5600-52b6-44d7-84e8-d7b1c6e964cc/verizon_remote_control_code_for_vizio_tv.pdfIn PDF document text
    • http://dupivet.epizy.com/surugonupufiwu.pdfIn PDF document text
    • http://nopitoweda.rf.gd/arcade_games_apk_for_android.pdfIn PDF document text
    • http://fujalaliwedav.epizy.com/caste_certificate_form_bihar.pdfIn PDF document text
    • http://tifumego.rf.gd/28834607299.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b718508f-6b45-4373-9c45-3169f910d031/webaropukonivoxuvanaxilim.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b081314a-e61b-4ce2-aa2b-032d7fa20a38/26526230945.pdfIn PDF document text
    • http://xugivikiseb.rf.gd/70533023823.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_off0000df8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8A 5396 bytes
SHA-256: 116d83290b4c1688546a432e304651237513ac44068ce18cfefd99cc46946103
font_01_sfnt_off0000f1d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D6 11384 bytes
SHA-256: 1789b3248dcb5449060080b8ad53137a3347a5b7089caddc55c3128f23222658