Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b5518f2992f8172…

MALICIOUS

PDF

87.7 KB Created: 2021-09-13 21:00:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2b23052ec6e0e3aed337f085215c42b8 SHA-1: fefcd630c6bd6ebc1272d47c39e17c9f13cdebe3 SHA-256: 5b5518f2992f817241e11ca09f6dc9a66f5f26ab933979d4ddd4a776e1755b7e
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to unknown PDF files hosted on compromised or disposable domains. The document body is unreadable, but the presence of many external links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://darkoyunpin.com/calisma2/files/uploads/67391942732.pdf In PDF document text
    • http://karpatskiles.ru/store/files/fojibetufoluvovagu.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210912055734.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/rarugezonomuga.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/53590416906.pdfIn PDF document text
    • http://turagent007.ru/userfiles/file/misevanexa.pdfIn PDF document text
    • http://xageunion.com/userfiles/file/ponapexotaxibidojetovujek.pdfIn PDF document text
    • http://cuacuonanbinh.com/userfiles/file/jevozidunu.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/24275669134.pdfIn PDF document text
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/94782446942.pdfIn PDF document text
    • http://myoffice2561.sesao33.net/UserFiles/File/19105029326.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/12500291846.pdfIn PDF document text
    • http://southerncross-ex.com/images/blog/file/tidumupuzisosolasolij.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/pupud.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358e54d5b37---wunavoxodejuvabugutagol.pdfIn PDF document text
    • https://www.creativetalentnetwork.com/ckfinder/userfiles/files/sonoget.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/58152319240.pdfIn PDF document text
    • http://eikenhorstgroep.nl/userfiles/file/26384538954.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/161367b7858cef---84287076238.pdfIn PDF document text
    • https://businesslife.com/content/files/17474313134.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/67ce55d36bqh7unuh8ab1dastt/kigamo.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a65fa03590---34568640912.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=up+to+date+app+for+androidPDF link annotation
    • 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_off0000f545.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF545 17168 bytes
SHA-256: c4a84ff5d0efab5cbb36815715f93ec655ea99e77b7cf44686d243259824e97d
font_01_sfnt_off000121b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B2 10284 bytes
SHA-256: 70e20b47f02395f36c72b5521fa69108968a0f7220b8a35adf77f2b881add974
font_02_sfnt_off000138ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1