Malicious PDF — malware analysis report

Static analysis result for SHA-256 4836b7ed0f348f08…

MALICIOUS

PDF

83.4 KB Created: 2021-09-21 10:32:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 02e947705ebd067fd9b1fbdef378f8d9 SHA-1: 20f181451d6e18fd590d7fb29828245b7b53d58c SHA-256: 4836b7ed0f348f084e34f14385de6e58c0223bb3778b77bbcce27c6bb013efac
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to compromised WordPress upload directories and other disposable hosting, suggesting an attempt to distribute malicious files or redirect users to phishing sites. The presence of multiple unknown URLs reinforces the malicious intent.

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 http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137190981f5b---40577081842.pdf In PDF document text
    • http://neoneofitou.com/ckfinder/userfiles/files/dexofizowikigubapemu.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614445b65c246---94435026127.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/rewodileberifibojiwuwebov.pdfIn PDF document text
    • https://nurea.se/currency/userfiles/file/42261622294.pdfIn PDF document text
    • https://digireg.lu/upload/jojamafutaxarudobidabuvap.pdfIn PDF document text
    • http://bighost.vn/uploads/userfiles/file/3749441163.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/jezogotowav.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/8f0234db081e5bd3bdb8ec2ddf778228/56555978440.pdfIn PDF document text
    • http://edisonprivateschoolbeta.com/cote_dor_import/admin/ckfinder/userfiles/files/tenutifobuzewusekov.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/visafadeziwerodopibum.pdfIn PDF document text
    • http://ctnphrae.com/ckfinder/userfiles/files/tivumawaf.pdfIn PDF document text
    • http://straps.by/ckfinder/userfiles/files/rowanotasisisov.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a45bfa9c6e---vefegorabiwiwepeno.pdfIn PDF document text
    • http://888spirits.com/userfiles/file/lekometiripora.pdfIn PDF document text
    • http://quaint-house.com/images/blog/file/pufataket.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/87186549367.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/modifunegiwasutifekedatan.pdfIn PDF document text
    • http://sedaciesupravy.sk/media/file/vubobiw.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/fazisi.pdfIn PDF document text
    • http://nazycakes.com/userfiles/file/66363648614.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614090c1d1384---bomajokani.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=gta+san+andreas+install+mobilePDF 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_off0000e153.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE153 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF965 17904 bytes
SHA-256: d6e7309694a8ec7ec73c6d2f8f1384633ab7cc8ee7fefb190d1c5098faa4c932
font_02_sfnt_off000127e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127E5 10588 bytes
SHA-256: 35d62b3c9d87a2b32ebff0b7b0e091110bcc23a39eaed950e6eddf4c5b612445