Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ad79e72caa13ed1…

MALICIOUS

PDF

82.4 KB Created: 2021-09-04 16:51:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 38bb18edcd4ece5bd63c2266474615e8 SHA-1: 2beae526df0027849f26f8c424c0c9a752671228 SHA-256: 8ad79e72caa13ed188e877d6c3fb91c9af2ef8875d817658e4611008d0339f2b
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. The presence of numerous external URIs, many pointing to compromised CMS upload directories or disposable hosting, indicates a link farm designed to obscure the final destination and potentially distribute malware or phish for credentials. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://bienbao.org/uploads/files/badafoberopoka.pdf In PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/dd63627e5ea18edc5e2b633f1c468b2d/84100249108.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/9b2311bafeccc0824e1373197c1bf827/34233249302.pdfIn PDF document text
    • https://grandegroup.net/files/89139683302.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/cc4mffoha98m7q64o1d3fbedir/gakitatodilewav.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611940343cf31---marutixesivusegodoxe.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/luvumotavakixijumemonil.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/161148c3927192---leborurixex.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/33f6f9d42433787e3e4b6e11656600c1/wezinuwu.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/g3vt5hkju9d1n1inr9qa7o6bs0/6023366340.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/gijosivolivutarapa.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a48dee7391---2132485250.pdfIn PDF document text
    • https://hoangphatdanang.com/uploads/image/files/puposanomugabete.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb11059dbe---45334190829.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/f6hmqhlq0pb2lobc542081c618/putamuxafiteri.pdfIn PDF document text
    • http://mosvag.ru/img/lib/file/36028961687.pdfIn PDF document text
    • http://technoauto.jp/js/upload/files/32578802391.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/46198880172.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160765f07a3c30---46042986531.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/nalugalogiximime.pdfIn PDF document text
    • https://fanaf.comarticle_ressources/file/mozatenetofad.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/fs2h6sirhmm3ma1grepm2d2cv0/96466358864.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/flh3cjmsta88a6qkbsk7auot52/68564296550.pdfIn PDF document text
    • http://okudshava.ru/userfiles/file/85931653199.pdfIn PDF document text
    • http://to-kajihan.net/js/upload/files/dexusen.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=tratamiento+lesion+manguito+rotador+pdfPDF 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_off0000dace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACE 10904 bytes
SHA-256: ea14cbfb3b6fd3cd7297f7ac8bea1333c93d70aef11f9f6a2b59633e314dabe2
font_01_sfnt_off0000f3cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010bde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BDE 19224 bytes
SHA-256: e11a2ed2eedeac1e64d2ede13024a6c0467a0042d8c222c3c5e6e925622c1fbc