Malicious PDF — malware analysis report

Static analysis result for SHA-256 911a0167c229e36c…

MALICIOUS

PDF

83.4 KB Created: 2021-09-05 12:03:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 32fc88da96019beb500e9a4094894550 SHA-1: b5116908d7d509719436abfddc8cdfdb36e12216 SHA-256: 911a0167c229e36ccf1cdc95062bcfbc68b778116131106c37d5d2970d0d7a1a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing or malware distribution. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic confirm the document's purpose is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://uleshuzataruhaz.hu/files/file/zegejuseloratin.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e35512e5b8---57619580593.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/539db45e9f7472786b634eabbdbb8884/watimewewatakupoxid.pdf
    • http://tolltisztitas.eu/userfiles/files/xipuxiwufololuv.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612417d58edf2---sipugubofa.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/91343831ffcfea34790bd735537c32ad/bajuxelupob.pdf
    • https://willes-gb.com/uploads/files/202108140431569262.pdf
    • http://botosani.ro/img/uploads/file/vujagosizis.pdf
    • https://cuisinescartier.ca/upload/editor/file/livijofisowixa.pdf
    • http://chanakol.com/ckfinder/userfiles/files/1054465459.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1c279934e---86737055441.pdf
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gujejurogafe.pdf
    • http://tai-group.com/upload/files/duzepo.pdf
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/c0afc069cc203949f462c1cc09bbb951/wefemufuw.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16075603b10a2b---kusimurafosuxagi.pdf
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609ffb22230ae---27783624734.pdf
    • http://cobansut.com/userfiles/file/94401844822.pdf
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/41121234861.pdf
    • http://ct-tci.com/cttax/userfiles/files/69796619175.pdf
    • https://flardochform.se/userfiles/file/41793474844.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4d1189f74---61448368633.pdf
    • http://eurolocal.info/sites/default/files/images/file/98043676056.pdf
    • https://helicopterleasingservices.com/userfiles/files/70138201395.pdf
    • http://jiuxingchaoshi.com/uploads/file/300716234533.pdf
    • http://3sdent.com/upload/files/29647603450.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16111e378304d9---guroresonuro.pdf
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/7562773238.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=reproducci%C3%B3n+sexuales+de+las+plantas+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcba.bin
c79df86b85a8f45b7de13a9805f0e9d52e447bc920eccc78b10638e9507fd2d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBA 10996 bytes
font_01_sfnt_off0000f628.bin
dba04eadc7473669c26bf34e34aa4f5f01ca1ee7fd465d0cd207a6d31497c52a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF628 18408 bytes
font_02_sfnt_off0001253b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1253B 16792 bytes