Malicious PDF — malware analysis report

Static analysis result for SHA-256 2281dc05bd4475e5…

MALICIOUS

PDF

72.3 KB Created: 2021-09-28 12:04:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 827c2e5bd2e2dcf01f84c447031a2baf SHA-1: 4b37a75de7a01a761183b7d078afcdc168a0d299 SHA-256: 2281dc05bd4475e52d2612c6948a8502d965d65a0afefdcda674594386146ab5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised WordPress sites. The primary purpose appears to be directing users to external resources, likely for phishing or malware delivery, rather than containing executable code directly.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://marblo.com/app/webroot/img/files/2741488743.pdf In PDF document text
    • http://studioriggio.it/userfiles/files/finimuzotutevujolepozev.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614877c496b33---15256086367.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/jijexazi.pdfIn PDF document text
    • http://www.niceresidence.net/image/upload/File/9862549324.pdfIn PDF document text
    • http://master-stroi76.ru/userfiles/file/tozelazozilemumizukidor.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/26505077626.pdfIn PDF document text
    • https://webmedcentralplus.com/userfiles/file/zatijotu.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/91251508591.pdfIn PDF document text
    • https://v-rshine.com/upload/images/files/74116682706.pdfIn PDF document text
    • https://yuktogel.com/contents/files/folemebinaxulewaturex.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/97160204982.pdfIn PDF document text
    • http://ageofwonders.buka.ru/sadm_files/vetelikamiken.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/94809926534.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/pewudosorolobowezegidopon.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/gugemodapepug.pdfIn PDF document text
    • http://clinicaveterinariagussago.com/userfiles/files/56818962745.pdfIn PDF document text
    • https://g-stampo.com/pics/pages/file/5875622016.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/12094200482.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbd52186c8---56392116020.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea62766d87---watetolusibifodiwevuk.pdfIn PDF document text
    • https://stephan-kratt.de/data/reiterhof/userfiles/file/55609770585.pdfIn PDF document text
    • http://areopag-group.ru/sites/default/files/uploads/42561628754.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c779a0fecd---33989246891.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/79274328163.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=android+11+for+a70PDF 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_off0000b844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB844 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD056 17364 bytes
SHA-256: 34aeba42c81dde80c2597c113908e7626b126b6a9d2972910e4bca71a3585c9f
font_02_sfnt_off0000fcf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF3 10108 bytes
SHA-256: 94de9076eade6461937ab9d4c8f287a38d35a5c5e9b85b5bb42074f8faa1c422