Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d31797e03c109bf…

MALICIOUS

PDF

80.4 KB Created: 2021-09-18 23:49:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ae1a8ea92d531ddc26ce983a4360b89b SHA-1: c15b979540ac07d08a708fa57bf230eadb34349a SHA-256: 5d31797e03c109bfef8f8dd3783fcf74d6429572dc5e15bdb2770c30a8264603
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS uploads, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the embedded URLs are the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pistant.ru/uplcv?utm_term=lp+lucky+patcher+apk
    • http://sgrdinstitutionspandher.org/sgrd/userfiles/file/89836223431.pdf
    • http://viorina-deko.com/images/file/mipes.pdf
    • http://alpha-th.com/userfiles/file/83688514236.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/mebaneturemolafedutamu.pdf
    • https://kaptenhoki.com/contents/files/fipadulufaw.pdf
    • https://rh-h1tapi-turbo.com/contents/files/rojimizutenedozo.pdf
    • http://dvg.asia/ckfinder/uploadfiles/files/jezukojogusopakufimawelo.pdf
    • http://avesta-hmora.boj.se/uploads/userfiles/files/61473248197.pdf
    • http://www.cerel.eu/images/wyswig_images/file/ramasipememotafi.pdf
    • http://oroblupiscine.it/userfiles/files/57315737917.pdf
    • http://maurovalleferroarchitetto.eu/userfiles/files/danoveranugitilosar.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab5e3b7897---mulujet.pdf
    • http://haozuowenwang.com/imagefiles/file/sukox.pdf
    • http://ozkayalartrans.com/userfiles/file/71901865562.pdf
    • http://work4shop.cz/userfiles/file/xibeloloduzapuxowa.pdf
    • http://zxsolar.com/d/files/27206695360.pdf
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/63476392413.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d18dea1c33---debawegumelewenutitalole.pdf
    • http://diamant-x.sk/UserFiles/file/jexolusufutozo.pdf
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/77734456423.pdf
    • http://ettermanenterprises.com/ckfinder/userfiles/files/64499813061.pdf
    • http://ncfc.com.tr/ckfinder/userfiles/files/78381575897.pdf
    • http://harc-ias.vn/Images_upload/files/sefuzi.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/3b1rd4p91c774t0tgbg3e21bhg/91711333475.pdf
    • http://kdwatch.net/upload/files/2021091609261388.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_off0000d7c5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7C5 16792 bytes
font_01_sfnt_off0000efdc.bin
c27457e03fc7210518233e01c9b779a60dd6d8a967beb32ab57dadb667fea038
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDC 10252 bytes
font_02_sfnt_off00010722.bin
8b43b650e4b6ddfa7ee8ac777328826da2e7a5effb984732b95eb2b78aff456f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10722 17332 bytes