Malicious PDF — malware analysis report

Static analysis result for SHA-256 158ac7558e6df86a…

MALICIOUS

PDF

87.6 KB Created: 2021-09-01 15:06:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ef4e7269bf8627dd5af7b03ffb80ecd7 SHA-1: 4da1fd420d570773b7b0b94648d6a552b31fcd3f SHA-256: 158ac7558e6df86a1e3e61dd8a84ec6657f48f3e6f9037a9abc0f13073f57db6
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains and appear to be part of a link farm designed to obscure malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The presence of embedded URLs and the 'Download Button' heuristic further support this, suggesting the document is designed to trick users into downloading a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://dsverano.com/UserFiles/File/bexesijuwobupatavab.pdf
    • https://aljazeerahpetroleum.ae/userfiles/files/besevilo.pdf
    • http://hajnysport.cz/FCK_userfiles/file/xoponegazisajijimadapavus.pdf
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941f06a1059---35720902698.pdf
    • https://digireg.es/upload/12228202838.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7c933214e1---vegogene.pdf
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609859ff860ad---wuwetepupabevosapele.pdf
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/16097b037caa52---33774537734.pdf
    • https://iveducentar.com/uploads/assets/file/judukanizazakarajosiza.pdf
    • https://smartstone.ca/userfiles/files/17553175330.pdf
    • http://www.tokyomagic.jp/images/library/File/jobexorodod.pdf
    • https://nhorizontours.com/userfiles/files/zemapo.pdf
    • http://bobiniauto.com/userfiles/file/sovosutepabupetewedotefow.pdf
    • http://turhantur.com/turhantur/files/xuxakimusopalexunuliwa.pdf
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/da8tb88tgi861k04nffrq09cla/52872418024.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/s3j8valtkmfvnfhqt1ndjf44sd/zujuz.pdf
    • http://druckmaschinenservice.com/uploads/fce/files/5691846985.pdf
    • http://villa-carlshorst.de/sites/default/files/file/55685697690.pdf
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/160775d68f3e11---45494736844.pdf
    • https://villatoscana-pi.it/userfiles/file/dorowuxonomewuvuza.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a47fb95837b---nowikotopunowega.pdf
    • https://siroyensao.com/upload/files/makexaziwesi.pdf
    • http://siciny.pl/userfiles/file/midukurekeze.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=solution+of+concise+mathematics+class+8
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f17c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF17C 16792 bytes
font_01_sfnt_off0001098e.bin
61c680d9e1e0d671db8be8d689bc14025829e87c08d8f504cea3709d93fdba2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1098E 17704 bytes
font_02_sfnt_off000136c2.bin
70e442f214230a324edbbd660c384fb2239aa0dd5509119ae91206d0d9fb697c
pdf-font-stream PDF embedded font (sfnt) at offset 0x136C2 10884 bytes