Malicious PDF — malware analysis report

Static analysis result for SHA-256 227ee551a8c03108…

MALICIOUS

PDF

101.1 KB Created: 2021-07-13 23:10:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d93611f83f88b099482c7531a69e2b16 SHA-1: 6873303dc5164213addecc8998e54fc9bb57be49 SHA-256: 227ee551a8c03108ac7be3826d0b3bb4da02d6342818ff35388a7c56314c10a1
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier strongly indicates maliciousness, and the presence of these links suggests an attempt to redirect users to malicious content or phishing sites. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

Heuristics 5

  • 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://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160949e13ad3fe---99501612638.pdf In PDF document text
    • http://skiflogistics.ru/userfiles/file/vivoju.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607491ab32d5c---pofifemag.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/78845370223.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/ugibna38ae72p6g6mq1ntbbkvs/5193271195.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/97390339975.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080287a28248---texuvivu.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/05/13/file/20210513_224908_130.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e842a2191b---70529017743.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/dukaxij.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/57380729956.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e520589724---95919373975.pdfIn PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/14524680835.pdfIn PDF document text
    • https://patriciobanados.cl/upload/file/In PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/74880358358.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/rbvdqndhafqbp3jfaafujt7o70/11520562014.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b4b582140---loxizilosiv.pdfIn PDF document text
    • http://thetachikappasigmaalumni.org/clients/5/56/56ac51e2ee760b54d3ff8b7d53c877b7/File/21786371746.pdfIn PDF document text
    • https://jotelek.hu/files/file/20513943738.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/fozafakabenotop.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608679b169f48---59912663593.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/5b752dec4d4d5226d1edb8a3bbf7772a/44683053583.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/susodometo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=queen+of+the+damned+full+length+movie+freePDF 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_off000126e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126E8 18184 bytes
SHA-256: c99167429809ef0423d980a53d0ba2ec18d4d137e8cf81404117bc36509638e2
font_01_sfnt_off0001564d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1564D 10860 bytes
SHA-256: 2d5aa77c6645e0a1c4bc2165d996e98a3cbee80859620e67ec558b478828566d
font_02_sfnt_off00016f0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16F0E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1