Malicious PDF — malware analysis report

Static analysis result for SHA-256 761306326d5bb15c…

MALICIOUS

PDF

68.4 KB Created: 2021-09-26 08:04:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 030a29a154b89e9719876a4701a5f10c SHA-1: ff52bc1e038c308531946ef7fc12e1e116caa616 SHA-256: 761306326d5bb15cfadb2705a3079213612b4af995eba2a77d2438cf0ee6d743
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload storage, indicating a link farm designed for phishing. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious sites for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=nfs+heat+studio+apk PDF link annotation
    • http://weilandvloeren.nl/fckimages/mumid.pdfIn PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/wisetemaj.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/96706224735.pdfIn PDF document text
    • http://machulski.com/public/file/69823246909.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/c49pq7kkpq6lnh2ese7v6fp0qd/86887105637.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/mitoxuzenereripowarus.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/09/26/file/20210926_050502_137.pdfIn PDF document text
    • http://sinoorchids.com/image/file/36056623479.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/85193995607.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/vetavulederisukonezitel.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/387a5582d411e7433ecd5cbf99fa2a19/wizoxux.pdfIn PDF document text
    • http://clingac.com/d/files/57785049918.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/518b0095f96bee1dd9db39de99ebe9d7/limojobokudafu.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/14652943518.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/lonobuxepive.pdfIn PDF document text
    • https://olterus.info/contents/files/8633034917.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/1238984638.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/55391810463.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/silapagim.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dff33b69f7---23294962059.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_off0000abba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xABBA 16336 bytes
SHA-256: 886aa3b8466b0c980ba84316f17cd46eac6171130788fa42891b1533d6502b62
font_01_sfnt_off0000d4a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ecb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB9 10512 bytes
SHA-256: e93d5c7c8981a0c94dac4e0eeae9aab825ad3ed0e2abf7020be5f48a1a48278f