Malicious PDF — malware analysis report

Static analysis result for SHA-256 f83d50e2aed8b2db…

MALICIOUS

PDF

69.1 KB Created: 2021-09-11 08:50:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53d96cf1416797d282031c4a3f1c65bb SHA-1: c769418b3a03edfaa0259b4c0bf438c393e8501d SHA-256: f83d50e2aed8b2db610fbd5bc64920b74daa4a1fe4dbd271bad3db4ceee7609d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as a link farm. The embedded JavaScript likely facilitates the redirection to these external sites, which are used to distribute further malicious content or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • 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 https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613940ebdbd67---sobomegokebed.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff08f312bb---88745298386.pdf
    • http://colantuono.it/userfiles/files/68915798366.pdf
    • http://www.asap-recruitment.net/upload/file/lamifabiligiweku.pdf
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210904005630.pdf
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/fonaf.pdf
    • https://akemi.ro/hirek/file/75495118809.pdf
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/d1ebf4af68e1f5046259d39c9934d17f/kejiwedubatedawag.pdf
    • http://lhdrum.com/User_File/UpFile/file/20210905100820_dnV3YWRhanVsYXp1ZGF0dXNpcGlnb2t1.pdf
    • https://next-engineering.com/userfiles/files/72782735024.pdf
    • http://ozkayalarlojistik.com/userfiles/file/juwiz.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/161391c2cd0697---ganolabirozomigeteri.pdf
    • http://dailymaytrogiang.com/userfiles/files/29030033110.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/9a07b527ee2080ba900f8311934849b2/51795975808.pdf
    • http://somkuthyoptika.hu/editor_up/pofalisamawatudorile.pdf
    • https://spcinternational.in/ckfinder/userfiles/files/65828673183.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ce0a33b84---mazizumazadi.pdf
    • http://studiopignotti.it/userfiles/files/panemefabamorubigobo.pdf
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/26289754847.pdf
    • https://people11people.com/uploads/File/feriwoxowitegikap.pdf
    • https://fiscalonline.ro/app/webroot/files/userfiles/files/80884469730.pdf
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161349eef93be3---sagizupixufuxiwu.pdf
    • http://vattucongtrinh.com/userfiles/file/17463215928.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=applying+properties+of+integer+exponents
    • 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_off0000b0e7.bin
28b590a1676e9385082af3edb1cf5fc557fd0a338c897144a21c55d0520e09bb
pdf-font-stream PDF embedded font (sfnt) at offset 0xB0E7 15084 bytes
font_01_sfnt_off0000d67b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD67B 16792 bytes
font_02_sfnt_off0000ee92.bin
df18d5553eac86d90cef025068f18199b734e8e06332cf3bf2fc0ca2856c388a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE92 10568 bytes