Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8b8ae078cd2d01a…

MALICIOUS

PDF

88.0 KB Created: 2021-09-15 22:32:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 25b47766e73c23c0914d329de2262d22 SHA-1: 015499a1b353b43a568ed65a6d050aa7f974612e SHA-256: b8b8ae078cd2d01a77116e711757c8f341c0deaf33957b9925bbc1a4f33d6b1d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1204.002 Malicious Link

The sample is a PDF document containing embedded JavaScript and a large number of external URIs, many of which point to compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing or malware distribution. The embedded JavaScript likely facilitates the redirection to these malicious links, which are designed to lure users into downloading further payloads or providing sensitive information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://crysiq.ru/uplcv?utm_term=batman+the+dark+knight+android+game PDF link annotation
    • http://centrlita.ru/archive/image/file/62128658226.pdfIn PDF document text
    • https://mlmrockstars.com/ckfinder/userfiles/files/setuduzefo.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/baf9db05fd24c863f86f327706edb76d/47664390759.pdfIn PDF document text
    • http://kedehg.com/ckfinder/userfiles/files/rusidizusunurazi.pdfIn PDF document text
    • https://ristovski.mk/public_html/upload/userfiles/file/begebuzijobajagabariwugaj.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/fugajagimavasudafi.pdfIn PDF document text
    • http://nbmounts.com/userfiles/file/1630740972.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132702f4dcfd---finuvenubinewolugiwiv.pdfIn PDF document text
    • http://orenprom.com/img/account/file/53869982648.pdfIn PDF document text
    • https://073741256.com/uploads/files/202109110657063002.pdfIn PDF document text
    • http://sjccgy.com/userfiles/file/20760944273.pdfIn PDF document text
    • https://maciejabramowicz.pl/upload/files/file/vixusonupufitulapep.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/suponu.pdfIn PDF document text
    • http://plusk-car.com/js/upload/files/zopuniw.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/netutozovogofak.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/mipow.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/70975265617.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/dapologuvepokukug.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/wigevujedinig.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/mcjrmie2s8e912o1u8643op30m/31889943814.pdfIn PDF document text
    • https://nic-irq.com/userfiles/files/40168151274.pdfIn PDF document text
    • http://kreativitaet-stadlhofer.at/global/images/userfiles/file/98830833827.pdfIn PDF document text
    • http://avesta-hmora.boj.se/uploads/userfiles/files/xuzanom.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/cc59cf516e6405fa6d95f4fff4fbbffe/xasabegopevekexemutagegud.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_off0000ea2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2D 21668 bytes
SHA-256: dc612c52081e9a1b3dc520649a99df1948eb2d3173b31566fa5f79c2058f98d6
font_01_sfnt_off000122db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013af2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AF2 10624 bytes
SHA-256: 5c35cab7d38c803c8b4a49263d64392de4c7cf4089ae6777bbe2274d77185401