Malicious PDF — malware analysis report

Static analysis result for SHA-256 23bbfc53485a986d…

MALICIOUS

PDF

75.6 KB Created: 2021-09-04 02:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 85dd5a790d25bb5e58a0f73f6a70e06e SHA-1: 4d99c35066617845bb798e3bab2eb600c3fc3331 SHA-256: 23bbfc53485a986daad70b76454c7e02eb29b46519c432da5262d574525cdcda
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and link farm patterns, suggesting it is designed to redirect users to potentially harmful websites. The presence of compromised CMS upload links further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://laborke.ru/uplcv?utm_term=science+worksheets+for+grade+1+living+and+nonliving+things
    • http://finance-bulldog.cz/UserFiles/File/vanazob.pdf
    • http://sage-chem.com/image/files/20210822_075112.pdf
    • http://www.alborada.es/ckfinder/userfiles/files/76982221040.pdf
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160824d7960529---debukunowitilel.pdf
    • https://najlepsze-w-polsce.pl/uploads/panajedotegakozovixuro.pdf
    • http://maasmartcity.com/userfiles/file/dowajopuwetokamovogi.pdf
    • http://dentherapia.hu/files/file/18516410333.pdf
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bagutasimozo.pdf
    • http://cl-pub.com/files/files/39494728467.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16092e46c2a1cd---xuwuluribubis.pdf
    • https://hmanagement.net/userfiles/file/96324519567.pdf
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/51693097844.pdf
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/db729d9t96lbgns3f4n06rau57/fajagoboz.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076334bb0a89---mepiruradikugumolijo.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160819605ca118---20596357858.pdf
    • http://aprt1day.ru/file/79418903141.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ace7cd3cff0---xolulepasuluvejifewiwi.pdf
    • http://sanarina-coaching.de/ckfinder/userfiles/files/xomuza.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/2897fb05d26be5170d253781e491b182/55728987636.pdf
    • http://mondoacquapiscine.com/userfiles/files/bivimuxelavetoremulan.pdf
    • http://dush-kz.ru/uploads/fck/file/76979469834.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/k2oskl94icqslbdqh31up9md2r/91740520211.pdf
    • http://thedewakohchang.com/image/upload/File/4380202210.pdf
    • http://topenglish.sk/app/webroot/gallery/files/netujilajo.pdf
    • https://anup.bo/images/files/31674538488.pdf
    • http://romanakladatelstvi.cz/userfiles/file/suzuxebedokazo.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_off0000c46d.bin
ad04ec854db791aea0603bf262306906f52411464876f13fee59969db051bece
pdf-font-stream PDF embedded font (sfnt) at offset 0xC46D 16120 bytes
font_01_sfnt_off0000ede8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE8 16792 bytes
font_02_sfnt_off000105ff.bin
dc74477ecf4317499801ddc942259bab95c8c8d0c33eba84e6c173c69f4feb33
pdf-font-stream PDF embedded font (sfnt) at offset 0x105FF 11124 bytes