Malicious PDF — malware analysis report

Static analysis result for SHA-256 f30740cabb674d16…

MALICIOUS

PDF

99.0 KB Created: 2021-09-02 21:10:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9687de88564d0b21957aa7ff6ad9f3ee SHA-1: 2dd95dbb21e4285018a607edf3ff04b6172b6c23 SHA-256: f30740cabb674d16e27d81cebce391e5ee0acd4cbe395439fac004f6fadbf8f2
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised WordPress sites hosting other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple PDF_RANDOM_URL_LINK and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms the pattern of linking to potentially malicious content hosted on compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://sosonomo.com/ckfinder/userfiles/files/64995492748.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f90e90b030---81690188457.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/fliqpq4unficfc6anjgq01bbo4/puwamodaxufa.pdf
    • http://spodne-pradlo-2bpoint.sk/UserFiles/File/61662664410.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c71b632f60d---zirexapiwabugubu.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/5o007pos7v2vqggo42i0pilal2/nijiliwelad.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/befef1020219383449d80d12a0598d78/nivesuwezifisixij.pdf
    • https://cqhuaan.myhost360.cn/upload/files/08-31-07-52-07-58.pdf
    • http://thedewakohchang.com/image/upload/File/ipinokefa.pdf
    • http://peoplefineart.com/assets/202107/files/20210721045445847254.pdf
    • http://smartvoicecom.com/userfiles/dadobovozipusa.pdf
    • https://rosanaalvarracin.com/userfiles/file/sopavijubesovazadewewadap.pdf
    • http://www.valathors.com/ckfinder/userfiles/files/33480036112.pdf
    • https://fibra-optica.ro/ckfinder/userfiles/files/vedeteburenadafizatosidod.pdf
    • http://silverleafspa.ca/clients/10619/File/27458578648.pdf
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0717/1be8c39d592313b069ac7fdd98d84693.pdf
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce805131b2---40941984203.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/ht9ialr7ec4l98bk92gvpetba6/mufisetigijodisudilujume.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070bdba0ff33---98491971999.pdf
    • http://meble-tk.pl/userfiles/file/66908537934.pdf
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ebebc54a73---josiwobete.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=service+manual+honda+jazz+2009
    • 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_off00011ab0.bin
fa6df55f99a4218cb0908a62d6605e05f87915a14242c48f70c7cc7265ec2bf4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB0 11208 bytes
font_01_sfnt_off000134c3.bin
dc54e5296c62fa51673f9fc3b15e525d0d2bf7d8b2a7f75a3143c2f5559e2c38
pdf-font-stream PDF embedded font (sfnt) at offset 0x134C3 18496 bytes
font_02_sfnt_off00016514.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16514 16792 bytes