Malicious PDF — malware analysis report

Static analysis result for SHA-256 113ea82eb255af8a…

MALICIOUS

PDF

80.7 KB Created: 2021-09-13 20:31:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5a6b7f2df5a2c494ee30d712a6266cc2 SHA-1: 1d466bb176567943ad879ed67abae2efb3ff48b9 SHA-256: 113ea82eb255af8ab09b589e75d0e150766f871fe3b3e56b9f9dec401bff45a4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://aqualibramontois.be/fckdownload/file/taposuvex.pdf In PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/87641670249.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/71190010829.pdfIn PDF document text
    • https://vyrukrc.lt/userfiles/file/79434605561.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/93588645601.pdfIn PDF document text
    • http://euro520.net/userfiles/file/16308799471717485090.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/161300b523e1c2---wekikesuwolefuboz.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16132817e31743---56499084430.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16132f2af716ad---7554274614.pdfIn PDF document text
    • http://musicpark-live.com/userfiles/file/muxobeweluginijul.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/6eb6df6c886a28000402ad6e38de846c/perewufuvikojis.pdfIn PDF document text
    • https://mygoaltv.org/ipp/images/uploads/files/15845533708.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/zufeninewo.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/tikinuwuvovu.pdfIn PDF document text
    • https://endeligmandag.no/e-brev/data/div/busokewigomunil.pdfIn PDF document text
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/lawobikiwu.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090317430070554.pdfIn PDF document text
    • http://freeware-software-download.de/uploads/editor/file/68538316820.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/88563729452.pdfIn PDF document text
    • http://runo34.ru/attachments/file/palube.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/048f071a5570b030ff6edb3ebd1f0166/puxof.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/55850514915.pdfIn PDF document text
    • http://wernitznigg.at/files/11191038410.pdfIn PDF document text
    • https://ghnservizi.com/file/4159571243.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=switchme+multiple+accountsPDF 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_off0000d566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD566 10800 bytes
SHA-256: 3df101ddd1c66abc9d30b019d13e2dc3f0bde701e7e964c089216095915723d6
font_01_sfnt_off0000ee27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10639 17892 bytes
SHA-256: d1524b24af36dc280839c305c705d0347d8d08f3d245484722c9754f255e63a4