Malicious PDF — malware analysis report

Static analysis result for SHA-256 871f7550c39f4bc9…

MALICIOUS

PDF

83.7 KB Created: 2021-07-09 11:52:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d526bcbbcbbd48557444632fee17fea8 SHA-1: 77556038c7fbdbbdbaca20f50529bf171a0b3416 SHA-256: 871f7550c39f4bc93195ca83ab59a262fe5c3e5a79e796531db0b7856348a0cc
96 Risk Score

Malware Insights

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

The ML classifier strongly indicates maliciousness, supported by heuristics identifying the PDF as a link farm pointing to compromised WordPress uploads and disposable hosting. The embedded URLs likely serve as lures to direct users to malicious sites, potentially for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/b127248f1bbacf29980dc6f6a9033136/9573144289.pdf In PDF document text
    • http://laweasy.kr/userfiles/file/95344589065.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/jumutetadorutewusovu.pdfIn PDF document text
    • https://senhewood.com/d/files/zejoduxinusisogavuwinewiw.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16075edb00a9e0---jalavoji.pdfIn PDF document text
    • http://araonline.hu/uploads/file/bixikodawazib.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a166637136---7008592047.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608253d90f6bf---fedifezuwejofel.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbd51825f5---rimedukoj.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/240953e1kfitenl75i302vu666/fogavuvejinavoturilop.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/2966491279.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/nopunadasidexer.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a547096c8---57034873235.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9ba044db84---tupisar.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e17fd3df22---rufosak.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/badisulowonatisuwanob.pdfIn PDF document text
    • http://abwlondonblvd.com/uploads/files/rufeborifowikofupedag.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1607f6f8201bef---pevefinubigeg.pdfIn PDF document text
    • http://schnauzermountainminiatures.com/clients/17729/File/mutep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=showplace+12+traders+pointPDF 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_off0000e1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1CC 17660 bytes
SHA-256: 586645479e81d097afbcff139af8b59b59d90a4d53c1a6e4a8e57eaf7ea9a664
font_01_sfnt_off00011054.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11054 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001286b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1286B 10944 bytes
SHA-256: dbbc3a5c8e391aaef75c7c3722732adcf98dbf2a0e10b52242c37c36f8b6c351