Malicious PDF — malware analysis report

Static analysis result for SHA-256 b91ac86b1daa71d9…

MALICIOUS

PDF

96.6 KB Created: 2021-09-19 17:00:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0673b70241d5972b89477c1a11aeef19 SHA-1: ae4d91b99fc9bfd1fe24b20a90e5437430959d2e SHA-256: b91ac86b1daa71d90c95385befd12caa742a441e873e4bee095a587e6f42baa1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. It contains embedded JavaScript and numerous external URIs pointing to compromised websites and link farms, suggesting it's designed to redirect users to malicious content or download further payloads. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9879

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://irlanc.ru/uplcv?utm_term=android+rootkit+scanner PDF link annotation
    • http://malbreil.com/userfiles/file/67155760966.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161384efb8bfb9---ruxiginipigo.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/12236586106.pdfIn PDF document text
    • https://garraldaarquitectura.com/garralda_userfiles/files/16466337412.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16138dee1cbd33---61864998409.pdfIn PDF document text
    • http://ossokahve.com/upload/file/71341185408.pdfIn PDF document text
    • http://skyrun-arser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210901130932617389greu5h.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16138326504c95---28082951949.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/1745495459.pdfIn PDF document text
    • https://mailing.crpm.ch/ck/ckfinder/userfiles/files/93147279212.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/rerafagaxugotaruxez.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/givovaloka.pdfIn PDF document text
    • https://bliznacite.dvsportbg.com/files/junugiloro.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/13878505607.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/vugimuwunupowo.pdfIn PDF document text
    • https://alansglobalservices.com/ckfinder/userfiles/files/153290101.pdfIn PDF document text
    • http://lasantitosrestaurant.com/userfiles/file/tejiganorejejokovosorosiv.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/xulilavimasosebemosa.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/siletivawamapo.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/19122595439.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/99900263074.pdfIn PDF document text
    • https://himarco.ir/basefile/himarcoir/files/xetexipodalikujesubapizij.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/99648606583.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1612f34173322c---45293846888.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/worifamavutimiga.pdfIn PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/gepojej.pdfIn PDF document text
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/fepezamokedev.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_off000111fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012a13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A13 10392 bytes
SHA-256: 908d8c81863c6e9fb4bd55943126d044928fba5d8d34ff7215a1b3f07cfdf904
font_02_sfnt_off000141c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141C8 19724 bytes
SHA-256: 9498c85718d5b0c84a8cbf1626bc4342934990d0dfca2405acaecf71cbcaf705