Malicious PDF — malware analysis report

Static analysis result for SHA-256 d544cbd56790d65b…

MALICIOUS

PDF

72.7 KB Created: 2021-09-12 16:22:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4e936a59e6f2c5f55b83312c2e613070 SHA-1: d8d3a94ab0436f0efb0a55aa1fb5d362b5ba01b9 SHA-256: d544cbd56790d65be81c7d354a39e2dc675e82fb888b93e08afc58cecdbe7711
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to redirect the user to one of the listed malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=once+upon+time+in+the+west+full+movie PDF link annotation
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613977c485882---39056836497.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/16684350601.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/15246741689.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/89092393100f3f40b5fe318745dc591e/xawuvuwaretafivatemazi.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/c6ec67cb837e00f6a473639046eba42b/xevimifo.pdfIn PDF document text
    • http://hhsmelt.com/upload/files/dubanovisafox.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/videdaledidedu.pdfIn PDF document text
    • http://www.pzkexie.com/up_files/file/92742873516.pdfIn PDF document text
    • http://xn----dtbsgbucafmmaf.xn--p1ai/servimages/editor/files/welefixe.pdfIn PDF document text
    • https://pmapmc.com/userfiles/image/files/15142888039.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210904211242.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/lokox.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/fikezazamupovamu.pdfIn PDF document text
    • http://domexpo.ru/up/file/8092518946.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613367f74cada---dagureku.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/fanepuxizimalalav.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/jupabetanuj.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/1266157282.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/bizutejewoxoluvifalobegik.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7e41e457d---36311277942.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/80735077149.pdfIn PDF document text
    • https://777mto.org/contents/files/54562110092.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_off0000b8df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8DF 16896 bytes
SHA-256: a127e108705445615b821639126a60968732e655e0f3c747784f5b0493dd63ab
font_01_sfnt_off0000e47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47B 10760 bytes
SHA-256: 77e2a92c136ef38a00fb140f3428449a2ccb5b4ca2c5d2115271d9a612584177
font_02_sfnt_off0000fd2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1