Malicious PDF — malware analysis report

Static analysis result for SHA-256 4558c991eb6ef1c6…

MALICIOUS

PDF

82.9 KB Created: 2021-09-02 12:01:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c66ae2dc15ab114f4654a38c0c550f49 SHA-1: 44940237cbdf6cd7e00c3953afd07f1c643a29d3 SHA-256: 4558c991eb6ef1c6e57aa2663f7ba8782877ff563ae67e40d6db0613ccc55fe5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Additionally, numerous URLs were found pointing to compromised WordPress upload directories, suggesting a link farm designed to host and distribute malicious payloads. The ClamAV detection and ML classifier further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://davcpundri.com/css/file/1044758615.pdf In PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607840efce1e9---18328776866.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/33489418293.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/76ead0b6d50f221b9e735333de46c537/misawapopasigudise.pdfIn PDF document text
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/09db8575fe1e1a85610da33ea99ea3f2/77240039976.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/6e164a8069dd4ec577d946abcfdccca7/timuvovutikevapa.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-29/20210429115756216608.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/2c4f76545e671522c8dcd246aae9e04c/namizovajewekinor.pdfIn PDF document text
    • https://btegypt.com/file/47479292814.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f96df6b201c---45213290464.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/sofesa.pdfIn PDF document text
    • http://personnelstrategies.net/userfiles/file/34117307901.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16096261e4a154---wikewalolejezejulivawone.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/zutonukanufe.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092425a396f2---69014128027.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/bolilos.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfa576be5eb---21461217177.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/36762204936.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///91493333590.pdfIn PDF document text
    • http://aurora-c.jp/files/files/galedenu.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/mifidezuserape.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/jobowoxazipekemazug.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/daa28226b9a37a15b70c2fd80937425b/78489108358.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/j8o6nk9mo9oea1i9bpmt0nc7l3/bulogabamebavesebefogato.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/7fb7a712c5bc2a034e2b3f7ed2f3e8ce/repifigeze.pdfIn PDF document text
    • http://idolyokocho.com/js/ckfinder/userfiles/files/kexifukubuvagod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=plural+nouns+grade+3+worksheetPDF 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_off0000dac2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D4 19380 bytes
SHA-256: 39993e6a8e74f65d3cd3c24febdfa6f7735e4196e1efe4db996b52084104717b
font_02_sfnt_off000124ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124AC 10888 bytes
SHA-256: 086cdeb4dd0bc4f591871ce95d0d6d208d0ed1f899547ebef87cf2803a870483