Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f36ffce03d00566…

MALICIOUS

PDF

77.6 KB Created: 2021-09-19 14:45:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b6692eb0f3259cfd7780c66dddad5404 SHA-1: f3a935d4c2b0747772f9f0cfbbbd8f10b85a1c0a SHA-256: 8f36ffce03d00566af19885e5f5bcb2e657a649bc55a8fb99d287eec1ab23770
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm. Several heuristics indicate that these links point to compromised WordPress upload storage and disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://drafthe.ru/uplcv?utm_term=battle+cats+hack+download+ios PDF link annotation
    • http://coniperfumes.cl/js/ckfinder/userfiles/files/xajetarokoxurebagiz.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/49111746670.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/ogarumirar.pdfIn PDF document text
    • http://bdsductri.com/upload/files/11097316723.pdfIn PDF document text
    • http://glavis.biz/userfiles/file/dunelazite.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/35100873014.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/52116915629.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c496eb491---fovukafevebug.pdfIn PDF document text
    • http://rent2day.ca/ci2/userfiles/files/nevulelulefifubifen.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109040914554599.pdfIn PDF document text
    • http://angelofthewinds.org/ckfinder/userfiles/files/72545726621.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312f0212a3e---botexisofelixopi.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/17947803718.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210906170159528.pdfIn PDF document text
    • https://lose-weight.tw/upload/files/82117311457.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/murupozexage.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161456801297ad---zazonura.pdfIn PDF document text
    • http://standardamulet.com/files/files/gixuzo.pdfIn PDF document text
    • http://makeyourpartnermelt.com/userfiles/file/nerosurekuni.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/82952244120.pdfIn PDF document text
    • http://fiumevivo.it/userfiles/files/98553910261.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/rejobazesam.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/lenot.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_off0000cc74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC74 16808 bytes
SHA-256: 35ebbede6a0d74408f1c09c3f6688923491485689e9f5761a2006e51127c3c3f
font_01_sfnt_off0000f810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF810 10600 bytes
SHA-256: fcdc1e9102cb70680fe0860d65e48f5e0d347cf4cffee0861106a67deb5e5623
font_02_sfnt_off00011056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11056 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1