Malicious PDF — malware analysis report

Static analysis result for SHA-256 6cc8717dd0589976…

MALICIOUS

PDF

77.0 KB Created: 2021-09-15 22:35:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 27e115e6253b6ad41560a7196a5ba269 SHA-1: 6c1f091758c71b75ebdbb22325ebd13a5e995a01 SHA-256: 6cc8717dd05899769cfbc770079f8306a435e5e8038001ba26cbd731787a2e59
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. The embedded URLs, such as 'https://cructi.ru/uplcv?utm_term=fb+lite+older+version', are likely used to distribute phishing content or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • 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.
  • 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://cructi.ru/uplcv?utm_term=fb+lite+older+version PDF link annotation
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1613076aa49761---11732678316.pdfIn PDF document text
    • http://rund.cz/UserFiles/File/gugubipapewefurebum.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/walitebubimotakijavugosa.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/watirusomivak.pdfIn PDF document text
    • http://mdtrend.hu/files/file/kimawilokogasim.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/89697499018.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/gilutewosamewana.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd820b7002---tamidiroxew.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210906205402.pdfIn PDF document text
    • http://devveb.net/userfiles/file/fanilozilolesadojufifelem.pdfIn PDF document text
    • http://crescentcarpets.com/userfiles/file/jafopizatajukalodisokusiw.pdfIn PDF document text
    • http://grandfiltr.com/files/file/jowiriteduwojez.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/95245926900.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16137666f6cb39---xeludedusubozelov.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/vamugeridus.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8004bc8ff---70441215904.pdfIn PDF document text
    • http://mcrlclient.gilcom.ro/ckfinder/userfiles/files/38517202560.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/79679507905.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202109081949174358.pdfIn PDF document text
    • http://synhbio.com/upload/files/25683286846.pdfIn PDF document text
    • https://mcq.bmtinhoc.vn/InteriorWeb/images/images_news/files/89688927997.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_off0000cb9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB9F 17168 bytes
SHA-256: 9b124e9803b4382fa5ace6be3c4b54c94f6b8763478a68258f0b3906a4f65353
font_01_sfnt_off0000f7d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE8 10264 bytes
SHA-256: dc5be1d8d321acf25a73aab4cc031ca1115537a27b3890fd0b6e25c105863c20