Malicious PDF — malware analysis report

Static analysis result for SHA-256 710c251ef3385ad5…

MALICIOUS

PDF

98.8 KB Created: 2021-09-11 04:05:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1115044af15d9c1be6c3ac73e9d04800 SHA-1: ec2e1c0974654e8b20509fdbfbb0b793ab8d14f1 SHA-256: 710c251ef3385ad508cf758278143d9aa19a5835ccedce83f45031452c087a08
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous external URIs, many of which point to disposable domains and appear to be part of a link farm, suggesting an attempt to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect the user to a phishing site or download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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
  • 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 http://warwick-ems.org/userfiles/file/mejewasidefe.pdf In PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3659e0372---ratipazalulozukipi.pdfIn PDF document text
    • http://sjmhospital.org/files/js/ckfinder/userfiles/files/raxan.pdfIn PDF document text
    • https://tepatsasaran.com/contents/files/18112823482.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b967a058af---sixalisovilelusukapo.pdfIn PDF document text
    • http://muabannhagiare.net/images/uploads/files/11656655701.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/65261234927.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/77282246319.pdfIn PDF document text
    • http://shamayachts.com/upload/file/pemizisiberuwirojovifexo.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/86295920228.pdfIn PDF document text
    • http://tvsatkrosno.pl/userfiles/file/24274213467.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/kinukapupel.pdfIn PDF document text
    • http://flairpens.ru/uploads/files/majizesojozumufod.pdfIn PDF document text
    • http://tochuchoinghi.org/files/3147026025.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/73200668622.pdfIn PDF document text
    • http://ausafe.net/images/art/files/85563264004.pdfIn PDF document text
    • http://topliving.sk/userfiles/file/jafinatogitatija.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/23472177140.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/juxawapimajufanujif.pdfIn PDF document text
    • https://tmtteks.com/files/kodegubezofivadefe.pdfIn PDF document text
    • http://elpijisystem.com/file/dosibumojanolese.pdfIn PDF document text
    • http://tjchenxing.com/filespath/files/20210908113550.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109060219255575.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=instagram+hacker+v3PDF 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_off0001188f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1188F 20176 bytes
SHA-256: ee42bc4647c6a0cbc220e761d3df09babb2a63c66a8603d6df1a2c48a3be4289
font_01_sfnt_off00014d68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001657f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1657F 10700 bytes
SHA-256: 2352a33674d6c3188d901c46a61a88c0768c0ad00725a7ed1c3dca297d9f3cf7