Malicious PDF — malware analysis report

Static analysis result for SHA-256 d16ac2fc73ee8840…

MALICIOUS

PDF

106.2 KB Created: 2021-09-06 06:03:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 785564f29d8643dce11402b17e361f3d SHA-1: bfa46f19b07c159f37c42c67c4dc59fbcd6cc265 SHA-256: d16ac2fc73ee88406611f751884e063489374573c530de7758421d1583bf9743
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous external URIs pointing to compromised websites and potentially malicious PDF files. The presence of multiple external links and the compromised CMS upload link suggest an attempt to lure users to malicious content, likely for credential harvesting or further malware delivery.

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://crysiq.ru/uplcv?utm_term=ardhanarishwara+stotram+in+english+pdf PDF link annotation
    • http://okna-stv.ru/userfiles/files/pajebirepofabesi.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/96540758532.pdfIn PDF document text
    • http://csc-028.com/userfiles/file/20210707082006_sg6vwg.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210831225939.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/dabbd071028599062102527c433ca7d2/75669284840.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/f37a346ea26d02fd956d6e8a1fbccf9f/legup.pdfIn PDF document text
    • http://sirmamedia.com/ckfinder/userfiles/files/46853605767.pdfIn PDF document text
    • http://mariamozharova.ru/uploads/files/54247077359.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/f9687895c7586ba70a82d0c032b81b93/46313583726.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/mifepuwipinuzulojok.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb77b0358fe---15803202202.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/96955676811.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/zuduvetutivigasobuwanunem.pdfIn PDF document text
    • https://gullyracing.it/admin/ckfinder/userfiles/files/vupivar.pdfIn PDF document text
    • https://srmhospitalities.com/images/bulk_images/files/10195095742.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089b52153e47---96020589115.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/taxudotewuzemorajoludifi.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202108181827485463.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/57167414389.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_off000135f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135F3 19880 bytes
SHA-256: 8ec45d621c1f37ebd58dfeaa7beb11ca2ba13db7222cc21e9df915ea482ffec5
font_01_sfnt_off000169ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x169EE 11012 bytes
SHA-256: a4f66eb38cbfa2a6eb66c66d1629027966e4e38c353d3720178115c4ae6ec196
font_02_sfnt_off0001832a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1832A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1