Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbf08856d72c982d…

MALICIOUS

PDF

73.5 KB Created: 2021-09-17 04:56:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 75e6f2352785363c90a48d9a397452ce SHA-1: 54d360e67284a4c511c8420fa24b8d8579519a18 SHA-256: cbf08856d72c982d99f6b005bc43957e3f7d5120e75a0f16ee397db77d2aa34d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple URLs pointing to compromised CMS upload directories, suggesting it's designed to host and distribute malicious files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further supporting a malicious intent to distribute malware or phishing content. The ML classifier and ClamAV detection strongly indicate maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 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 https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc6e5018e4---fisetemuwo.pdf In PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/f7f2f2fb9af003ee39df4f47bdb86faa/pizexitilulupel.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/selojego.pdfIn PDF document text
    • https://tavcam.com/upload/ckfinder/files/lunogexulikuvax.pdfIn PDF document text
    • http://duancanhotot.com/upload/files/wogegusubako.pdfIn PDF document text
    • http://agriturismocorteerbatici.it/userfiles/files/taxujogewapoxuvuje.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/bowovaxasi.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/bibawebuzuf.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/udpgqaljmdu6p10keqe6uv1uk4/gifiretojamodurananuzu.pdfIn PDF document text
    • http://safaraval.com/basefile/safaravalcom/files/99525993145.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/73156335346.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/kelodizuxebefumupofufep.pdfIn PDF document text
    • http://stavo-bazar.cz/userfiles/file/70847613101.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/vizafivika.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23602934187.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/72844301159.pdfIn PDF document text
    • http://biomax.shop/filespath/files/20210905063830.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcf3ed49f3---4503419423.pdfIn PDF document text
    • http://marketingnews.fr/images/file/83367716490.pdfIn PDF document text
    • http://engineersclasses4competition.com/files/others/28324014477.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/wakafufuxob.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/99202984872.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/9257347bb0993eb76bd6c1c22c8a6f69/74318131753.pdfIn PDF document text
    • https://groupekineconcept.com/userfiles/file/61565533558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=grammar+translation+method+authorPDF 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_off0000bdc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDC2 16752 bytes
SHA-256: c55f37d6384bf4d09661f1d6e9eb7735c39a298b3e5f81aca84ba1793372bd5c
font_01_sfnt_off0000e849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE849 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10060 10652 bytes
SHA-256: e112139468d9ad5b07c5e3557f2fe64f338923327e0ee240222ab5382e8721bf