Malicious PDF — malware analysis report

Static analysis result for SHA-256 37a512e49eff7768…

MALICIOUS

PDF

84.6 KB Created: 2021-09-21 00:08:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 55237f35434225f520039e4d85eda19e SHA-1: 3af4578f0f6e26dc574a766563573e7ac3d90e45 SHA-256: 37a512e49eff776846c0a2b381815746ddbfe99933df58e5553901bb510cf6e4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and using UTM parameters, indicative of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or malware distribution campaign, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://laborke.ru/uplcv?utm_term=hot+movie+app+apk PDF link annotation
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363ef3ec560---jefumufuv.pdfIn PDF document text
    • http://trip-sale.ru/userfiles/file/32963833688.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/35c5c41360bf555a84a4ca1004c162c5/zagokexez.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/mujotikikutifurize.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/88311196738.pdfIn PDF document text
    • http://wedding-box100.com/uploads/files/202109080726161532.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/sevuforavirurizi.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/8919875168.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c05cd092e7---94064065894.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/pepekoxomizolekorelesu.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/87111661048.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021090613342073499.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/82845594255.pdfIn PDF document text
    • http://ctnphrae.com/ckfinder/userfiles/files/sopigijikatasozubaza.pdfIn PDF document text
    • https://izr.fr/files/kitumikunenonilibixamovag.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/75734891167.pdfIn PDF document text
    • https://galedo.cz/www/data/cms_files/files/56454509420.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/e732f16b6e8fbd22a8e9fe02e0644e5c/vaxijumapasebutemomedakak.pdfIn PDF document text
    • http://mim2010.ru/userfiles/file/37322887529.pdfIn PDF document text
    • http://dmkaudit.sk/101/upload/file/41330778257.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16133e836ad6a5---25239481142.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/55761609130.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_off0000e56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE56B 18432 bytes
SHA-256: b607123df955b11661e08bdc62979a3b897b5799423ac5aacb4cdcadfe1fccc4
font_01_sfnt_off000115c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012de0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DE0 10144 bytes
SHA-256: e2b217fa1ca0132c55834a1edf7027bc080f600685c70bf70f67c5f9534a9dd1