Malicious PDF — malware analysis report

Static analysis result for SHA-256 a712bfe8d3ccd801…

MALICIOUS

PDF

111.2 KB Created: 2021-09-08 06:18:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dc951e7d609d8cdce52c20ebbff2ec17 SHA-1: 4aeb4f6e1e8eefffc5930ba93ea3e05782b9679b SHA-256: a712bfe8d3ccd80129de71191444f203fc3790524b478e6f41b7b1a6a6bc08e8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the presence of link farms and compromised CMS uploads, suggesting an attempt to distribute malicious files or redirect users to phishing sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://kssi.ir/public/userfiles/file/781880794.pdf In PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/f2a5b0dd3890fd6f1e00fc105efe7f39/samavaga.pdfIn PDF document text
    • http://benevolo.it/userfiles/files/17644126275.pdfIn PDF document text
    • https://cargotavio.ru/files/file/seseberizorureraledafez.pdfIn PDF document text
    • https://path.mn/userfiles/files/didujivebibi.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/woperetumekatotekewaravaw.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/misefuwizeku.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/37446211418.pdfIn PDF document text
    • https://4appsoftware.it/file/nazowunizebaw.pdfIn PDF document text
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/60370985427.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/28848576100.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/21032018132.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/bovibamipibavikerukabe.pdfIn PDF document text
    • http://vakaruinzinerija.lt/userfiles/file/jobivuninuzimujo.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e2c289020---526676641.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/6474294041.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/5932175812.pdfIn PDF document text
    • http://greenhousehotel.vn/uploads/image/files/5314344272.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a729df2144a---20569224151.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/tovij.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/f7d9b2b628624ac5d277784b676f15cc/wuxevisox.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/14226370316.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/dizanulavuxume.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=trigonometria+e+geometria+plana+pdfPDF 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_off00014343.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14343 22248 bytes
SHA-256: 8d6248f5e6dfc7ba33b1a21fa42a0f8c3ab98de13a8185c34e063d6a87b73eaa
font_01_sfnt_off00017d73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001958a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1958A 10636 bytes
SHA-256: d4697ff557cf241093946c4c41d301e8ffc5c163e1e9ec9b2d2d059a0e379a62