Malicious PDF — malware analysis report

Static analysis result for SHA-256 666d57dda65c82bc…

MALICIOUS

PDF

101.7 KB Created: 2021-07-19 03:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: cebeb367d020afd2815fbb39c1f8e622 SHA-1: 471ad68d198dc80c1cad8de52d2a689806fd9d85 SHA-256: 666d57dda65c82bcb7abecb36792368c4a96ccfd173c94522f6981c9b57d4ba8
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lure users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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 http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abbf3396ed8---20423141212.pdf In PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/ai981ipbamhmjbeckk6ge28mnm/furivipajalo.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/74301703125.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/rimisefagenitevapod.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e37dadbbab8---regaleralemeliwuzaj.pdfIn PDF document text
    • http://luingpyrex.cz/foto/Image/file/20278804208.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/zevikusovunigubigupabij.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160ba40b66cdb3---49771750400.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/56683793995.pdfIn PDF document text
    • http://dade666.com/userfiles/202106file/2021061119543370554.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/301f513ec4885a14744364766ce020ed/kijifof.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160915a5ec153e---20581959114.pdfIn PDF document text
    • http://teraval.cz/res/file/63118807466.pdfIn PDF document text
    • http://atek-ent.com/upload/file/77258737680.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160da38e52ad0c---kutisunopebirudejomimuk.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/8a465d91ae22dae3292d6f9d2354899d/65042796875.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b35594237e7---35691976297.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/5113f38db91316aa2180db167bbe8eb4/sugunubebetumafujate.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a596b64796c---56941014943.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/dqgn0miutksm772agvadbrpncm/89757153040.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d1ecdba4a---butoji.pdfIn PDF document text
    • http://lindseyderence.com/userfiles/files/55083124831.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/bijinoru.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098593c4ed85---moxomenoratazusuxore.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/vpi4p9uqhscn668osd3povem7h/pomapagebudubebesuwase.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=ip+man+chinese+martial+artistPDF 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_off00012ce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE3 17208 bytes
SHA-256: 2f022811ccf3eaa83e8392b75c6025dc18801dff108a47b4fdc8011a3374a42a
font_01_sfnt_off000159c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000171dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x171DC 10468 bytes
SHA-256: 824d535dcf27a71b8e559e9e7064bf105627cd47517918cdff30ee4038ef7f50