Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f06134df1fea5a8…

MALICIOUS

PDF

76.0 KB Created: 2021-09-07 15:04:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fd1859b58f61a70f79c42d749f618938 SHA-1: d149281bfc80445ce52a375f7f3579d513663a60 SHA-256: 4f06134df1fea5a86aa45da6903bf69ac12960091d4d6137895aaea7f35480ef
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded links are indicative of a spearphishing attachment used to deliver a secondary payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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://medvor.ru/uplcv?utm_term=allen+neet+books+pdf+free+download PDF link annotation
    • http://csim.jp/ckeditor/uploads/files/81508399602.pdfIn PDF document text
    • http://stasta.com/userfiles/file/ruxuvonotuje.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/retotilo.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160ee0b8440402---bifimapa.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/3d060fd6a7ed63b44e9a83d515c289b2/fizigiwu.pdfIn PDF document text
    • https://gesema.com/UserFiles/file/18015359392.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/vo2rn2vco2vrcvs11s4vv0arbf/gakonazuzegoguw.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131c1db8b595---faraxorugemudedigefajatal.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16086e94264944---90024633076.pdfIn PDF document text
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/gaxipepaxuwafarazix.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d07317731c---95594140809.pdfIn PDF document text
    • https://dd-inside.de/userfile/file/xanaxozanudelox.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7c87127b58---38657072727.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160eca42491cf2---97373212206.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c6918d266---72885230088.pdfIn PDF document text
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/72fadf89f9424fdb238c09f765f9f38f/wozizebinibudedelus.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3bc908eb6cc4f96026ebb3b49cdbe6c9/46510322261.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160815e475f2f0---beniwajinotutegodosejul.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/puxuwelizibafuvafusufo.pdfIn PDF document text
    • http://tfforming.ru/d/files/dibofetirixetaben.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/nawotuwarowoweze.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/f792d3bd18a91e9842f78a23ba168743/lizovejunojenalumu.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/40644204728.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/wepoxobasemulizo.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://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_off0000c598.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC598 10696 bytes
SHA-256: 611731c988452c91084e1f693ca9a3ff20a2c7311623e3113ec3ea2258d6d43b
font_01_sfnt_off0000de2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f640.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF640 17192 bytes
SHA-256: ba22b8c0b34f68efc9eced30c09f1f9c731a9757898a1c06790d60791ee59056