Malicious PDF — malware analysis report

Static analysis result for SHA-256 c81d44581bcbe11f…

MALICIOUS

PDF

83.8 KB Created: 2021-07-10 06:49:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ecfa19225c6aef7520d4c3a68b67299 SHA-1: 4264bda7109b2ec09df02f7f7fb303e939e858c5 SHA-256: c81d44581bcbe11fa76d5a2a6254e916f7cddd804930044904582a09b5ce1a0b
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting it functions as a link farm. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised or disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://casier-a-bouteilles.fr/file/kiwuletorusokutagivugunal.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16095765ee8a22---68208357831.pdf
    • http://phuquytravel.com/nguyenvanlinh/files/nijexowasudifunageg.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/11uuufi9opdveh3glt86iio7di/rorawemalifon.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609113c839ab6---xubobowenufadulatin.pdf
    • http://agcslohian.com/userfiles/file/64773840510.pdf
    • https://tyeetomsfishing.com/userfiles/file/buziboro.pdf
    • https://fizjolech.pl/userfiles/file/buboxujokivelelukab.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091015c7a9b1---lobakezuxunudubopuniva.pdf
    • http://yorkiematch.com/clients/6/65/653dc45b8f6063886304ac4260dbb99c/File/momosatafigegupiwotos.pdf
    • http://beergolfers.com./blog/images/file/51997725505.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d16f74a1d0---25181034957.pdf
    • http://10glazsikeyrosa.ru/file/vazat.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983972db0bd---60382504833.pdf
    • http://sammyuriasproperties.com/userfiles/files/4327797760.pdf
    • http://chayka-svg.ru/files/mizisijazozulufutil.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160729d74578ea---33480220290.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/bk279cndvr0rpoirtmoeqfhple/dixanobaj.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/477f647acdd29e10a50e00b057da5370/37499878521.pdf
    • https://atcotourismtravel.com/userfiles/file/zewogelomovomagagumezum.pdf
    • http://bsp-oblspl.org/ckfinder/userfiles/files/lalabupapu.pdf
    • http://rsst77.ru/upload/files/piwafusejafuxasere.pdf
    • http://nutronicltd.com/userfiles/file/33485267281.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/af8142a48c8456c933425c72b489925e/18240132860.pdf
    • http://karunb.com/UpLoads/files/vevufezulabesod.pdf
    • http://longvu.vn/Images_upload/files/53528882352.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=full+hd+video+player+for+windows+7
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C4 16792 bytes
font_01_sfnt_off0000fddb.bin
ca2bbce45096af5efde8396a21b283301cd7b4a3779759918d1510734a7ebe3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDB 10892 bytes
font_02_sfnt_off0001170a.bin
ec11e0d76b0f77472c5447a7b854bc12a083a251e544ac9d6887a0781d13e0c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1170A 16464 bytes