Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb6848d9c87db958…

MALICIOUS

PDF

84.3 KB Created: 2021-09-09 02:54:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 475b4a9f7d0e7116c51d1dcd9b715952 SHA-1: 8d8d3fdd3edef270fa4ee51e26ceac63f1313a99 SHA-256: fb6848d9c87db958660179685e05e60b990ada7eedc89e9809b556515853ed2d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised CMS upload directories, forming a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery by redirecting users through these links. The presence of embedded JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://infrive.ru/uplcv?utm_term=cricket+19+apk+android
    • http://clickvay.com/upload/files/26650580143.pdf
    • http://savitaco.com/uploads/images/files/dazikurovotolarixetizexek.pdf
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/butoletoxevepigirazira.pdf
    • http://rinsacars.com/files/others/botidun.pdf
    • https://momentous-inst.com/uploads/image/files/xonobevinimo.pdf
    • http://honmamon-s.com/img_seminar/userfiles/file/varijezobaripiwufida.pdf
    • http://dalnoboy.org/data/filestorage/upload/files/85712826277.pdf
    • https://doktor-ara.com/userfiles/files/lodexafisaxet.pdf
    • https://snapstudios.ca/userfiles/file/fuporijodo.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032db69ff2---mitorujuwilovap.pdf
    • http://ckm-machinery.com/userfiles/files/dopofifulojub.pdf
    • https://weborder.cloud/userfiles/file///sirowumegodunevijezir.pdf
    • https://wic-net.com/userfiles/file/23949129188.pdf
    • http://sun-green.be/ckfinder/userfiles/files/50360367352.pdf
    • http://ekorob.pl/userfiles/file/rebegisedeganapigiguvag.pdf
    • http://orzo.cz/uploaded/files/jivakomijogufofob.pdf
    • http://espacioschillout.es/images/admin/file/10034280926.pdf
    • http://wefocusdesign.com/upload/files/26484987024.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/dc0bdbad0efb222d996df99e3b2ccd8e/14785921398.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139461ebaeba---domesugejifamedub.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370fc02ce6b---63858201856.pdf
    • https://svarovanijelinek.cz/ckfinder/userfiles/files/63338155854.pdf
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/jilosoluzuxilupu.pdf
    • https://silatur.com/js/ckfinder/userfiles/files/10891090788.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_off0000e428.bin
f9e4d1929cbbd895bb179c5e1d3aa606bf276fb9b57225ed35bf67f78fddedce
pdf-font-stream PDF embedded font (sfnt) at offset 0xE428 18044 bytes
font_01_sfnt_off000112f3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x112F3 16792 bytes
font_02_sfnt_off00012b0a.bin
6a71b861e2496bf0d5e5cb0997256d01e816462a6857111e3e3cbd2386694990
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B0A 10636 bytes