Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f3e848d2b844e63…

MALICIOUS

PDF

68.7 KB Created: 2021-07-01 00:21:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: f796393ea2146e55f539b392d25a60d5 SHA-1: 75e89e495106c3bd7e9cb0928f27f70dde6e4939 SHA-256: 7f3e848d2b844e63be5e22c493bc79011c6f0561b6759e8525e84b3f8bf5d1df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, suggesting a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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.
  • 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://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a861ed5c10---jisoxu.pdf In PDF document text
    • https://atraba-holding.com/userfiles/file/vagariledumebepelatuvuj.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e2ba063ab4---katobububiwewoverali.pdfIn PDF document text
    • http://elitvorota.ru/f/file/donaxasu.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/b87p68kerfldsrp05dtuqchmh3/pasosamoropawamelo.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/28167639914.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/sunugixubiwo.pdfIn PDF document text
    • http://elitvorota.ru/f/file/53016862599.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/vukupot.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a76ff44f871---28977037058.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/fatubugejopimidalaka.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab94e3815d5---68540266559.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada7e23578d---74870278252.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/6a72ef76f4914dcbbab99cf16c8c8b3d/koxeju.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091a0db4949d---kozusovevemukuza.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/zufuzojevulenikelisewafew.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/63923472460.pdfIn PDF document text
    • https://smilepaper.tw/archive/upload/files/menedobulidi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=after+myomectomy+surgeryPDF 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_off0000af51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF51 14724 bytes
SHA-256: 8d2ed1f9b1698cced7db3145b4481368f41c4967dd353ffe52a05306871dcc2b
font_01_sfnt_off0000d48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA5 10472 bytes
SHA-256: ddc9d39610198f1d7a81ddef1c12466a839cd0fc77aa10ee43d6e4cc0cbb92ab