Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21e1250d9dff3e8…

MALICIOUS

PDF

86.5 KB Created: 2021-09-23 00:10:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 182eea578654e12ed7ccd0f5e39c891f SHA-1: d5377c141c518b7417196fc030435d03093e980f SHA-256: e21e1250d9dff3e80f754380780cd17c6da68d90662a78b297c70a33b37ca702
164 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 other PDF files hosted on compromised websites or disposable domains, suggesting a link farm designed to distribute malware. The presence of a 'download button' heuristic further supports the intent to trick users into downloading malicious content. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://wastran.ru/uplcv?utm_term=doom+apk+2019 PDF link annotation
    • https://satuldelut.ro/ckfinder/userfiles/files/36578365868.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/nafegaliti.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/2021919173356585.pdfIn PDF document text
    • http://stimatacasa.eu/userfiles/files/43247649563.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/borabinaliwiba.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/7400772602.pdfIn PDF document text
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/28314016645.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16130c7ce164ff---87690024259.pdfIn PDF document text
    • http://fruitvita.com/files/files/47143304682.pdfIn PDF document text
    • https://gestionarival.com/userfiles/file/53640263247.pdfIn PDF document text
    • http://daithanhnam.com/upload/files/movepupisubepevojubeboben.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/22069606992.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/sedakujivimetizejawul.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/26610724584.pdfIn PDF document text
    • http://www.veslovani-vsb.cz/soubory/file/17466024108.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/japajuwezoxivan.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137399eb2959---1980656316.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/12267893136.pdfIn PDF document text
    • http://rentaruedas.com/files/others/57684209420.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613efcc585ca4---99603258958.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/2109120112303959889807d.pdfIn PDF document text
    • http://bhk-aindling.de/userfiles/files/4693184072.pdfIn PDF document text
    • https://granitnet.hu/editor_up/70925456462.pdfIn PDF document text
    • http://tdbm.vn/upload/files/58269200625.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/49448346188.pdfIn PDF document text
    • https://www.thc.gda.pl/ckfinder/userfiles/files/pogebajonolesugubiroroxep.pdfIn PDF document text
    • 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_off0000eb9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000103b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B6 10228 bytes
SHA-256: 9cfd6ccbfb0c5b544662a302ae8830f95079e347debb9b90b4b2ca38aed5e792
font_02_sfnt_off00011ab4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB4 19164 bytes
SHA-256: bb840dee90ae42c0e1753061f7d76640ff205d64a63d8e6e1395068e69ae59e8