Malicious PDF — malware analysis report

Static analysis result for SHA-256 a101a7de6518935a…

MALICIOUS

PDF

75.0 KB Created: 2021-09-03 19:47:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 42c3cf198da1361a65b9c8aa4c1e164a SHA-1: 422241af9333e84222613365a357a11871d19d7d SHA-256: a101a7de6518935adb3581e38332d205c83ec429ad5a5cf8eae9c2ec9de45093
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDFs hosted on compromised WordPress sites, indicating a link farm or distribution mechanism. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs point to compromised CMS uploads, reinforcing the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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 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 https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa1f52fafb---30347114169.pdf In PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/1282cbb659e4b5fac8a4455c75cd974b/dotobip.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/fufizufifipavoxarenikad.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac0eceeff1---junope.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16096ce6912622---dufasexusujuvoxudadaz.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1995a82ff7---43961655815.pdfIn PDF document text
    • http://taiwanglassgroup.cn/userfiles/file/77160272412.pdfIn PDF document text
    • https://aldapa.eus/files/galeria/files/46560234397.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160933fe603f77---dubafiluzig.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e60181d9a---tatipuxejoneriterofetajix.pdfIn PDF document text
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/patenipeguxaf.pdfIn PDF document text
    • http://techbis.pl/files/file/sugimasu.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/jelozuwibe.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa504e0c350---gudurib.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16108bbdb43924---mapaju.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/neakqalht88inv4qh7i874m4r1/69949875930.pdfIn PDF document text
    • https://triptoboloyfoundation.org/editorsfiles/files/5688927822.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/senifejewereri.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609458489bfe0---fegeremimadogixabiku.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///2417387175.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16115c4944765a---53300885517.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d29641cb893---51272023963.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/ditobupenawelej.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/af84c30c1151a086834eff5a27f1ac9c/nirewatigisezasos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=vogel%27s+quantitative+chemical+analysis+7th+edition+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_off0000bdc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDC9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5DB 17824 bytes
SHA-256: 767af3f014e05d7c50b1be7ca5f3c36d29f6afa65a57bcccc50d36022a36caf4
font_02_sfnt_off00010373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10373 11448 bytes
SHA-256: b8f23a2e7e37ee4c71575df3a2dacbb24ae96feb87552cd67fe044e195a74199