Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c677b783907344…

MALICIOUS

PDF

100.7 KB Created: 2021-08-26 07:16:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1c2b9160e0754834277e298c2dfb2eb6 SHA-1: bee3edd114d71291a90dfd82f7f95261824b3b4e SHA-256: b3c677b7839073448be08e1eeeb8dcc2d79e148c927b0df10fdcea8773a3bef5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/nozibebilelesipenej.pdf In PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16081e7206fc54---teketub.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/71583137878.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/xogov.pdfIn PDF document text
    • https://fundreamz.com/ckfinder/userfiles/files/96750578621.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607014248bdea---kunujorofibesiz.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f346350d20---soloxanozijenuneti.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/8e12c92f9bcf033f7507261af0f75cd9/tozowozavorovarusaf.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/167df500f1eef2875d2db3ff295e3f3e/94798464906.pdfIn PDF document text
    • https://travolution.travel/wp-content/plugins/super-forms/uploads/php/files/1530417be00d1352ae2f574950500beb/65798753174.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pjrbheftvfa8o79aqns67qeua6/72401476462.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/1ea2643a0d6a1583b4892c68d270e3b3/mufifoporaral.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/fagasurat.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/40644204728.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/6967908512.pdfIn PDF document text
    • https://giverny-bkk.com/upload/files/rumezijibemezozumaxif.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/33ir2euqeecg3m3okt3n34f6go/6919850299.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16110c39c835d2---88504055325.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/4b5ec1b72d08fca4f173c77b70637372/53911352107.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096c749161d4---bokidaritibaguxaponepa.pdfIn PDF document text
    • http://tantos.jp/js/upload/files/midepif.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/do9th3is4llhde2ml87nqhp3j7/65533469674.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083b9187b479---nadolurolezokoketidivi.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/48296750763.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/gawisus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=vaginal+yeast+infection+while+breastfeedingPDF 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_off000123b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123B8 11064 bytes
SHA-256: c420a5af1271371b386a0e0ab278c1ede47e93127b1f6d1d98952c6d50551c5c
font_01_sfnt_off00013d4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D4C 17756 bytes
SHA-256: 3750efd03f979d86f58ca85a5e766d3594d7d444fd6c933f89c7db5b83f5ac65
font_02_sfnt_off00016bb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1