Malicious PDF — malware analysis report

Static analysis result for SHA-256 d708246c82d8f4f5…

MALICIOUS

PDF

116.2 KB Created: 2021-07-02 19:25:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 6411796569ff5955c0b7de7197271e28 SHA-1: 81d3adbf3f3182e4c742ceb8bc4aeec23b464e4e SHA-256: d708246c82d8f4f5ddd2ff42e46a4db52f026cc730c0776b265413379483b059
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous other PDF files, many hosted on domains associated with compromised CMS uploads or disposable hosting. This pattern is commonly used to distribute phishing lures or second-stage malware. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent, likely involving social engineering to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://instandee.com/Images_upload/files/74509810818.pdf In PDF document text
    • http://staresecurity.com/userfiles/file/lelido.pdfIn PDF document text
    • https://arerp.kr/data/file///46308293242.pdfIn PDF document text
    • https://mimpishio2.net/contents//files/35868258544.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/lemokediz.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1cac137b5---21365275870.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160b639f008713---15503083245.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/bf2ef7746c699db941d3a8475f628f36/zumakiwajijapurafewava.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16095a09376d27---nasakavufatigelolob.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210607045710119610s8tayy.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bacfd18b77a---77988170626.pdfIn PDF document text
    • http://www.klimavill.com//data/editorfile/novanekipusajazobu.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/vujisuwitunipoj.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/43226773560.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806bf840d46---togekorijibamuzex.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076c7c7526f2---89898905558.pdfIn PDF document text
    • http://darec.sk/files/files/xedosuratez.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/06/file/202106260530583102.pdfIn PDF document text
    • http://sterenstein.ru/userfiles/file/zexalofitadosatelunobaxe.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1606f19b61ac19---jusiwefaraboxefora.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/278b28d6c78d6a36d98bbf237e0b9b48/89658912494.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc1f358f4b---topitare.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/3039a65ba1469e7333e82858dc2fb699/82802121994.pdfIn PDF document text
    • https://led7.ru/file/44779851608.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a865f93107f---danedopilizirok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=brown+and+white+dachshundPDF 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_off00015b4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B4D 10660 bytes
SHA-256: 73e31e537e25f89225904df06c01b1aa2288a256d7a291b5eb67b8d246a3c7db
font_01_sfnt_off000173c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018bd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18BD9 22172 bytes
SHA-256: 0b31f49c79841e88b4a9e0f361d6fcbcd3bd9e410afb1abb0a557864a227b5de