Malicious PDF — malware analysis report

Static analysis result for SHA-256 037877f5ebf6ce5e…

MALICIOUS

PDF

74.4 KB Created: 2021-09-02 10:34:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: db64fc6c722efd9c182230a338faa2ac SHA-1: 311d8ec37042eae6684a59b874d1539496e278d9 SHA-256: 037877f5ebf6ce5e8f87f8697ba82316f47aa074e76dabe5d7bad46cea0ae8e0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable domains, suggesting a phishing or malware distribution scheme. The ClamAV detection further confirms its malicious nature, identifying it as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://elbag.net/wp-content/plugins/super-forms/uploads/php/files/c9b4540bccf194eebe618b8028397485/71605002825.pdf In PDF document text
    • http://jngf.cn/files/file/34910896098.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/gtcnatq6h32uppp1uiltek0hkj/lifuzanosax.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/siluzovakosuxexaxodavax.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612870bd04c9a---56910032939.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/14743907922.pdfIn PDF document text
    • https://daismene.it/file/lekaxudevukuvanamusunadal.pdfIn PDF document text
    • https://dongcohonda.com/userfiles/file/32132020039.pdfIn PDF document text
    • http://xn--sanitrprofi-p8a.ch/fckeditor/editor/images/file/zujakipovibojunolumesalaj.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/bivomom.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/gag23qju0ouf7cogphao727b6a/lesorevokevidejema.pdfIn PDF document text
    • http://mirsistem.com/depo/sayfaresim/file/vesojibupurododo.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/83f1f7c0710e31c79391251db8637f2e/kufirafimuriwizodagegusu.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/nanulumexibulot.pdfIn PDF document text
    • http://kroonzuivel.nl/ckfinder/userfiles/files/30827727645.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/jaxadalubamebuvabam.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/8c035ab9caccb1f85b8693a48c120aec/92968324639.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160866f430ba17---ditipemaxobakuwubaxaf.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/98dcc8874203377488819b1fa8c2e5b7/61208833442.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/80824812870.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/nevinokilakolad.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/1b9fbae613d3785587e2bdcf75ff1378/lisevovubesubujin.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ecf7ba969---tonelezusojamo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=d+%26+c+after+miscarriagePDF 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_off0000c139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC139 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d94b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD94B 19056 bytes
SHA-256: 66b681affaa38798f72a797f3a849e775dc11030a1838300cdabe6b1f9ab0824
font_02_sfnt_off00010ad0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD0 9076 bytes
SHA-256: f695977626623e59fedb2fbedebd468d0acf89ff6f6ceafeb3cee4351ddee6c8