Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9953bafa5832140…

MALICIOUS

PDF

79.8 KB Created: 2021-09-14 04:23:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1f1263f86bc5ae7ab872790b21e16ab6 SHA-1: c59ff56037b2bdae806f9ed792fae955c6b960db SHA-256: a9953bafa58321407f352b0de3746cd1049e8aab4e85994d75c92782387d40ab
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF contains a link farm pointing to compromised WordPress sites, suggesting a phishing or malware distribution attempt. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394c2bbc8b2---75292551640.pdf In PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/lsaah2j1spffvjfr23abgjl6pu/42707576681.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/161398402683d6---xafolasobira.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/xeguwosekuvitefenavoj.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/razefomik.pdfIn PDF document text
    • https://springkasteelhuren.be/userfiles/file/75102856954.pdfIn PDF document text
    • http://sedaciesupravy.sk/media/file/vexopesi.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/sebizapoxomizoxivefafoket.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-6/20210906033500438720.pdfIn PDF document text
    • http://bordahusfeldolgozo.hu/editor_up/vevonupovimakug.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/kusabofomelegukajudab.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/92113978786.pdfIn PDF document text
    • http://getrade.net/uploadfiles/file/38886886516.pdfIn PDF document text
    • http://www.neoneophytou.com/ckfinder/userfiles/files/78645161418.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/lujikuvejeditob.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4ccc85266---5224935342.pdfIn PDF document text
    • http://gcsiva.com/files/userfiles/file/69135778643.pdfIn PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210904_124613.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/3864179949.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/goxazegirazaruzorefe.pdfIn PDF document text
    • http://pradakshinam.com/fck_uploads/file/81473711561.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/68014721440.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=types+of+widgets+in+androidPDF 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_off0000d739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD739 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF50 10788 bytes
SHA-256: 1cf2e226a74dbe1b59852c62dbdedc4a18846b5e934e2dd834fd222c934a67a3
font_02_sfnt_off0001082e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1082E 16136 bytes
SHA-256: 490a8cf12242f902b0cdf6ddb76d660cdf49921fd6d3192509df6b5dba7b261e