Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ce79db99693b7b3…

MALICIOUS

PDF

83.3 KB Created: 2021-09-24 11:04:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 921008328c2595731441199dd16c2880 SHA-1: ae6d6e372df8fe5c5f92386c1cf37ae1b850641b SHA-256: 8ce79db99693b7b3abaed0bf7ff8b2999568dd4f0ef659346d052d5768875e4f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO abuse. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

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 http://myrbacken.se/login/ckfinder/userfiles/files/jifovulagaron.pdf
    • https://mn-lawfirm.com/box/userfiles/file/juzadejutawaxodi.pdf
    • http://stlukesfp.org/ckfinder/userfiles/files/29249649958.pdf
    • https://pamukoglu.com/userfiles/file/3864236907.pdf
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/18397471131.pdf
    • http://www.kevimotor-rock.hu/files/files/51286147586.pdf
    • https://langumeistras.lt/i/File/rudagasolujaxamupugugesu.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/5puprbe2evraaildsubd40e79n/36924483439.pdf
    • http://debschoen.com/userfiles/file/voxuvorujidufu.pdf
    • http://jyjwqj.com/uploadfile/file///2021090516035888.pdf
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/pasireralibexizuzabekusa.pdf
    • https://zaindu.drogomedia.com/files/galeria/files/50820262242.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0d9287d61---mesixitowejirutesun.pdf
    • http://karinameal.ru/imgdish/files/84017457831.pdf
    • http://russia-ex.com/images/blog/file/laxitavakun.pdf
    • http://adhunikjewellers.com/ckfinder/userfiles/files/gofibo.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/dab212392e01e2e2529bb2a04250b422/36279144887.pdf
    • http://richmore.kr/uploadfile/fckeditor/file/94260571110.pdf
    • https://sweetburden.com/upload/users/files/92903249052.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161426e802a642---31178143371.pdf
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/0ec7082473eeac8379ebb0732bc8a0c8/28546832357.pdf
    • https://aradmissions.com/ci/userfiles/files/74900968006.pdf
    • http://aeon-dev.com/uploads/files/202109230113102305.pdf
    • http://haai.org/upload/file/dafizudotanadi.pdf
    • http://wagnerpc.com/userfiles/files/87197375528.pdf
    • http://tryinvest.eu/userfiles/files/25149574084.pdf
    • https://bakwanudang.com/contents/files/rufilugujefi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=cara+install+android+di+netbook
    • 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_off0000e16a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE16A 16792 bytes
font_01_sfnt_off0000f981.bin
9dd49d52322b1a783834681986f8cea0d59645417e9bd1946d6cb9e2d1b8c8e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF981 10504 bytes
font_02_sfnt_off0001117a.bin
3580537215bd2a959024ef100638dfddc9a0c96289f3bcbb49e41d9ac49952fc
pdf-font-stream PDF embedded font (sfnt) at offset 0x1117A 17788 bytes