Malicious PDF — malware analysis report

Static analysis result for SHA-256 7013d3915f970d24…

MALICIOUS

PDF

84.3 KB Created: 2021-09-15 17:19:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 95d44e1a042bd4ab9ecf19ac4863e0ee SHA-1: 20fa816ae475a38fc76a6209d88138a7cfb8f3a7 SHA-256: 7013d3915f970d2407ff061eaebf79d48a44b7366a42282cdf8eaddacfcfbab2
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as containing a link farm and was identified as malicious by a ClamAV signature and an ML classifier. The document body was heavily obfuscated, but the presence of numerous external links, some pointing to compromised CMS uploads, indicates a malicious intent to redirect users. The primary attack pattern involves luring users to potentially harmful external websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.clinicaepilepsia.cl/ckfinder/userfiles/files/fojalivifowobaxepotuvujij.pdf In PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/68159092891.pdfIn PDF document text
    • http://hueide.com/upload/files/88780550957.pdfIn PDF document text
    • http://gurukripapublicschool.com/userfiles/file/ligapasij.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/walisamesuwolisomuvalo.pdfIn PDF document text
    • http://zgic.ru/!upload/files/dimagafoji.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/21559657745.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210913230720.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/gafimufuweraremawebirofor.pdfIn PDF document text
    • http://synfarm.com/upload/files/wolesiziwufuso.pdfIn PDF document text
    • http://yuqiaohome.com/uploads/files/202109032301192436.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/walof.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/338def291a405878d0ca4a16da8f2635/53130028697.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/tidumumejizok.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/161341077a342a---19378668239.pdfIn PDF document text
    • http://thevalleytrader.com/files/mapevonevaniseteki.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/15196067721.pdfIn PDF document text
    • http://holidayservicemarsala.it/userfiles/files/bituxomezejemes.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/74770693098.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/98842759744.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614112cca53cc---13156383902.pdfIn PDF document text
    • https://turasmobilya.com/img/editor/image/file/74131977376.pdfIn PDF document text
    • http://ordineveterinarireggioemilia.it/userfiles/files/90066754448.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/85448319931.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133606680e8f---18771894131.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=lords+of+mobile+cheatsPDF 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_off0000dca9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA9 10732 bytes
SHA-256: 831d85b971182fe898ffa9508acb7321a697d886282d32101221e3ce27decc05
font_01_sfnt_off0000f54e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D60 20924 bytes
SHA-256: 849efb7eeb14f26792513ac95280ed7f4ee7056d384f45683c100552955bdcaf