Malicious PDF — malware analysis report

Static analysis result for SHA-256 277ab2aea54a2386…

MALICIOUS

PDF

81.3 KB Created: 2021-08-28 12:09:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 85df2667f6a6d9ad74fd2dcd8abacfed SHA-1: e5c538e2d13f87ac13cd57ec61c1cb2a065956df SHA-256: 277ab2aea54a2386392be3e92223109105256882b01f1b49b9af2c141484a763
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document that exhibits characteristics of a phishing lure, specifically instructing the user to install a remote-support tool. Multiple URLs point to potentially compromised or disposable hosting, suggesting a distribution mechanism for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/ad0802bd5b45a2c607e1f3f927212c74/lofemesox.pdf In PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160cac9926ee9c---51700914230.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f2159f4a5---somegotamisokexoxaluderam.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/637818ba96a7cc9c0f369fd82d9d17fe/3437498884.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/50328046649.pdfIn PDF document text
    • http://alarmy-kamery24.pl/userfiles/file/jebiputini.pdfIn PDF document text
    • https://esportenerd.com/app/webroot/ckfinder/userfiles/files/nebalitolinipilegax.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5bb9657845---jadimo.pdfIn PDF document text
    • http://scro.ru/pic/file/nutebatiku.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/luxomivifajusev.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/gqff1vdo729kq3bqil150utji2/57292332558.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/5ea9c9d9791a5bb31d6ae953bfcaf9b8/migogadivugiden.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/v52dd4i1nipkka84gtjh3tjlf1/59938729798.pdfIn PDF document text
    • http://sartor.ru/upload/files/3920279578.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607caafd48bde---zaparomubaxorogop.pdfIn PDF document text
    • http://dsagco.com/Upload/file/68901764819.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/81813576087.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es/ckfinder/userfiles/files/felanimupesiwisimubifigo.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088072eaed7a---51173339018.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/92321590643.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608b7eca835f5---79533704487.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-25/20210525165537786364.pdfIn PDF document text
    • https://warungmimpishio.com/contents//files/kagedutatezidokilabaponir.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608e51a7a342a---26666881732.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610619d104680---92980973468.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=like+in+where+clausePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d76c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76C 18688 bytes
SHA-256: 9a415ffbf4346aba5bd09856d700ea0120a20b19b7f474073c9fc8f7549de00a
font_01_sfnt_off000107cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE6 10344 bytes
SHA-256: 9f0d027b555628edf81b79e1fdef452193b71e1fa363eba31908de12e750731d