Malicious PDF — malware analysis report

Static analysis result for SHA-256 da840753acd3c722…

MALICIOUS

PDF

84.5 KB Created: 2021-09-21 22:14:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: abd4089bad16c8a39e07800c7c164029 SHA-1: a13c19a11f17213de7d540d9f77a8b2d52741ac8 SHA-256: da840753acd3c722a6c482c786791dcebb7e8cc638009b6ed4b4142a9ee950e3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or delivering a secondary payload via the embedded JavaScript and external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://nomylo.ru/uplcv?utm_term=snapchat%2B%2B+2021+android PDF link annotation
    • http://alfadent-volg.ru/images_uploads/files/fixinizapubowidagefawupet.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16141218829006---76883604527.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/4597525176.pdfIn PDF document text
    • http://come2menorca.com/images/file/wodadugamelodumedosupoda.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30976839768.pdfIn PDF document text
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/74631772698.pdfIn PDF document text
    • http://dierenwinkelindex.nl/images/uploads/supewi.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/26735017135.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/wuwezexesewukejamamolu.pdfIn PDF document text
    • http://hidramaco.com/files/files/gamujin.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/xubixogige.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/f319fd825eaff5f428b8ff7dda427156/15400805020.pdfIn PDF document text
    • https://vargyasnekonyveles.hu/kepek/other/file/41292767025.pdfIn PDF document text
    • http://octapus.vn/images/uploads/files/43176253752.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/234486284.pdfIn PDF document text
    • http://sobateracota.ro/mm/file/kararimulubezejufebe.pdfIn PDF document text
    • http://benetalent.com/upload/files/53068047110.pdfIn PDF document text
    • http://balassalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/64253942163.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/as7n9cs6ktuffetp002uljvmet/povuminuzem.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/44238125853.pdfIn PDF document text
    • https://majubesar.com/contents/files/57981513299.pdfIn PDF document text
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/zabenevuliralo.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_off0000e4ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4CE 10636 bytes
SHA-256: c9d16cfeebcb0a56e174df7b1f51eb249b40a1bfac90ccd8676419a8248018e7
font_01_sfnt_off0000fd1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD1B 18576 bytes
SHA-256: 819a663bcc167c4650e01ffd3f950117483b4213cd4605827f03e79dba3d8452
font_02_sfnt_off00012c9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1