Malicious PDF — malware analysis report

Static analysis result for SHA-256 86ef4dfb093b6318…

MALICIOUS

PDF

84.0 KB Created: 2021-09-19 09:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 81fd99be060d30bb54a339f7d7de1c19 SHA-1: a7d274bcc1fea6308c4afe466ae1b0cf4768433d SHA-256: 86ef4dfb093b6318effe972155f404b1494df864e2265e4127899938011258c9
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on disposable domains and appear to form a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection to these external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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://aquatherm-graz.at/files/32573847009.pdf In PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/45a92f7b6da5b0aaed4fb0a6b0e2dcaf/76260378519.pdfIn PDF document text
    • http://lt101shop.com/userfiles/files/92630765535.pdfIn PDF document text
    • http://cybernet-ap.com/UserFiles/File/65266846683.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/fodiwifisusubavujo.pdfIn PDF document text
    • https://granitabrasive.ro/editor_up/zatilute.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/1613680f3591ca---rubilivonitiwetom.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021091410045073499.pdfIn PDF document text
    • https://milliondollardesiclub.com/upload_files/featured/files/48457354132.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/47864099315.pdfIn PDF document text
    • http://deleeuwputten.nl/site/data/ws/files/56480240104.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/ziwiripozijawosarawane.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a87fc6f8e---17240527106.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/data/editor/file/43641916775.pdfIn PDF document text
    • http://tvcsoltau.de/userfiles/file/32462448212.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/rijoz.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/58150206653.pdfIn PDF document text
    • https://ijpdua.com/contents/files/pakiremijiwowixomenoxusi.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/20392830715.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/runesudakaxoxisonaz.pdfIn PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/12905044238.pdfIn PDF document text
    • https://ketex.com/trcgp/ckfinder/userfiles/files/bopaperejadeza.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/63735398840.pdfIn PDF document text
    • https://aneri12.eu/res/file/45148579670.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/nupalizenuto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=android+windows+7+launcherPDF 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_off0000e41f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE41F 17684 bytes
SHA-256: 9e79ad205da4518e81c11d3bd6b108ef298b2b9985ee481572688f4e8aba7f98
font_01_sfnt_off0001126b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1126B 10584 bytes
SHA-256: ff8c508e2a5d9493b1761e0688bb36dbf69565160844004398cf22fa4c5b44d1
font_02_sfnt_off00012aa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1