Malicious PDF — malware analysis report

Static analysis result for SHA-256 8128a477b14d575f…

MALICIOUS

PDF

88.5 KB Created: 2021-08-02 20:49:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4089b296b2432025c151bccde0d701ae SHA-1: 7614a317363b137b30f3bd554a748979ed512819 SHA-256: 8128a477b14d575fa2db1b206c4a7c3e1cab0fea4dc4d10b20a312e69308a952
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many of which are hosted on compromised WordPress installations, indicating a link farm for distributing malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the presence of numerous suspicious URLs points to a watering hole or phishing attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b083338fee5---wulopoxane.pdf In PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6934a3b46---vufadufofisanenanujakejod.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16093c89c45a41---xudapezogodi.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/waloxozab.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/b8449d0cd277dea5b8457a85ea63e3b7/winuvotasib.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/dtas2s05p288rh6niraagg77nt/21486436487.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/oh9ajk2ejotpb8r84urkfmvo2d/36154192585.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1426891a5c---batikenutajatuposimaku.pdfIn PDF document text
    • https://speculatio.in/ci/userfiles/files/45024106953.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c648758fc4d---87241042438.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/ab5c4b7f6b5f637e0734d628569056fe/44646798326.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/6g1nvebb5vi08dm6jli0evqp52/64221314424.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/47997270721.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/nvd36in97houtb7p2vdgih94r7/78065305458.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a43ebb2a78---7669936369.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/68764ec23d56462abd8c6afd11e906a9/jobalosikolugadapenuzedi.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/6mb7ejdjdhk7cu34scf2le4gks/gabufitipevaxofaw.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/zagufikesifivirosutewekob.pdfIn PDF document text
    • http://wadirumshootingstars.com/userfiles/file///92664900461.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608122a2db8ba---fedudob.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/3890800013d7bbbe1bde892fb346f73a/dikulebumudax.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/hbe0vftdmg1e2o9dt6t6qmjfmt/42672096709.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/m34u1aq1ul9ae5h5aska3dak75/62140305669.pdfIn PDF document text
    • https://edusfera.pl/upload/file/buwosixapejizijipi.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160ce4714cca13---sagopijodawekowa.pdfIn PDF document text
    • http://steakclubhn.com/campannas/file/pafibujuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+can+i+get+free+2gb+on+telenorPDF 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_off0000f3a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010bb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BB8 10680 bytes
SHA-256: a6b8cea3a72ec2b348498b0831081b3a859cb842a3ce668c8b87d1571872e073
font_02_sfnt_off00012469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12469 17328 bytes
SHA-256: 336d6f67d89890c5539a746284f8e92db0d8ca98db7529f3b2ce62ad11988ca3