Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4b245c259c6c64b…

MALICIOUS

PDF

99.9 KB Created: 2021-03-12 09:15:21 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: f0d17a8b21ce62805127b9358b36258f SHA-1: 14e7cc5f9a780aa01b642e425dfec30b2abf33ee SHA-256: a4b245c259c6c64b5e639d805da1d071829bdbe1e9e12a46670178341211b64d
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 0.9994

Heuristics 6

  • 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 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://zajinet.ru/123?utm_term=new+orleans+jazz+trombone+sheet+music PDF link annotation
    • https://cdn.sqhk.co/pumurugo/ibCieoe/alarmy_app_download.pdfIn PDF document text
    • https://cdn.sqhk.co/lupobikud/qjdhgid/98596534671.pdfIn PDF document text
    • https://cdn.sqhk.co/mofosalamo/Sjf5Sjh/crowd_war_3d-_rush_city_games_string_cityname.pdfIn PDF document text
    • https://cdn.sqhk.co/dukosisevu/ShVicIN/espn_mlb_scores_yankees.pdfIn PDF document text
    • https://cdn.sqhk.co/sajixobuko/m9jjRx3/fuvidadujavewobanesage.pdfIn PDF document text
    • https://sowubewakojanit.weebly.com/uploads/1/3/4/3/134348505/af054c.pdfIn PDF document text
    • https://xenesadu.weebly.com/uploads/1/3/0/7/130739949/6559568.pdfIn PDF document text
    • https://cdn.sqhk.co/wakewafo/7D3iclt/93620115129.pdfIn PDF document text
    • http://laserisesiseno.getenjoyment.net/sezidotoras.pdfIn PDF document text
    • https://cdn.sqhk.co/wifepodilojo/fhjN3a3/jifumobolukokagimiwofo.pdfIn PDF document text
    • https://cdn.sqhk.co/keropolor/jjige3d/litafinogaxavanefobenu.pdfIn PDF document text
    • https://cdn.sqhk.co/moromasi/Gif4WT3/buzinexaxi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385020/normal_603e8494879d1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375209/normal_5ffa3cfd33e65.pdfIn PDF document text
    • https://cdn.sqhk.co/zatuwifezub/Jmjdjjs/jevufibiwomasopisuta.pdfIn PDF document text
    • https://renepavavoz.weebly.com/uploads/1/3/4/0/134012855/saparas-rakuxexuzizib-liwewonazejolo.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://gidubabe.myartsonline.com/sweetheart_bodice_pattern.pdfIn PDF document text
    • https://7a6021ad-ea99-40b3-bafb-6570e045b460.filesusr.com/ugd/527ec5_dc69dac190b844ca8a830b9f8fb58b9d.pdf?index=trueIn PDF document text
    • https://13a7c488-548c-4b48-b567-d2b0b9a3e1de.filesusr.com/ugd/85d67f_0fa98c73da63469fa48c96cf87299417.pdf?index=trueIn PDF document text
    • https://9e1e9198-0fe7-4103-8084-fdcc6befb8d5.filesusr.com/ugd/2f7815_5fa8df4f96164f1aa19611282989caf7.pdf?index=trueIn PDF document text
    • http://kenesowozowojaw.myartsonline.com/dolaj.pdfIn PDF document text
    • https://6afed14e-2b01-442b-8c2e-11a8a6f39965.filesusr.com/ugd/46a5ae_8c75af9d263f407b9f353f21c13c7c18.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013af9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AF9 5248 bytes
SHA-256: 50cd85ebaa16b88453e362bfa4153916b923d3bbd9874cd16fabfb6ad7e6a372
font_01_sfnt_off00014cc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CC1 11860 bytes
SHA-256: 6b5deb20e1ac33cd07665618e8e24938f9fd1a3f0e98511ae6e8a4304d5a6f32
font_02_sfnt_off000173ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173FF 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176