Malicious PDF — malware analysis report

Static analysis result for SHA-256 27fc10932d7f0d55…

MALICIOUS

PDF

72.7 KB Created: 2021-09-06 21:37:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6b354aa418e1366c4f846f865bd46ac8 SHA-1: c9f44929556a630747eb402e00f0858906350eea SHA-256: 27fc10932d7f0d5508d0fbe11c03ea414007d67f4f93e6971a46eb2345dec9b0
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier also flagged this PDF as malicious with high confidence. While no scripts were extracted, the structure and numerous URLs suggest an attempt to manipulate search engine results or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://dijladentalcenter-qa.com/userfiles/file/titunab.pdf In PDF document text
    • https://net-mex.hu/ckfinder/userfiles/files/zoladuzobibelenuzurele.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/waxubanepuferatete.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b11a302bc0---46794199239.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/c0ab003fa641185ad63ba7a66d22e6eb/vufogadudufesomurafabob.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/4lcut12j1d4fbbq2nqgmsqp6i7/86909471458.pdfIn PDF document text
    • http://crm333.com/documentos/file/faketetogupadikug.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/winumozunoken.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/vunaredot.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/76fd551ccee2b2e86294e21edffeb3bc/gekewak.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/93104917555.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/bosazogiwaputakefafuneg.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/nadezapudeparagilesit.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/895607f3e3c0a799a3889297f3988003/pojokebep.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160866b00df11f---15614954854.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/1579b4dab0e0bd2baa027211aae83b6f/69707718551.pdfIn PDF document text
    • https://tenfci.org/userfiles/file/91762182762.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fd289be8d---bipesak.pdfIn PDF document text
    • https://pingthye.com/userfiles/files/57520240530.pdfIn PDF document text
    • http://accronline.com/userfiles/file/sunarokuw.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/sobexewa.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/23988441795.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/d3e4215f77c5417aa185ab752e74e8ab/tulidusifotika.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084073e26a78---5372412050.pdfIn PDF document text
    • http://na3.it/misc/file/dikonokiri.pdfIn PDF document text
    • http://aaz.sk/editor_uploads/files/54682213242.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=voiced+and+voiceless+th+worksheetsPDF 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_off0000bab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d2cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2CF 10680 bytes
SHA-256: 77ed760f6fe0b02f50a5725b50f71fce7297e130a996c79558ab0b28d81adf8d
font_02_sfnt_off0000eb4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4F 16140 bytes
SHA-256: 7a72088b6e06a5a3c8428d0d297e59e77b0c1d81acd85473ac3d6adb0b0442de