Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb4e305ae3a0fbbb…

MALICIOUS

PDF

71.6 KB Created: 2021-09-12 14:04:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ea628eb20859b4f53332d899a831c50c SHA-1: 96e39e9ead221ea3b40994062d5bc598e282f34a SHA-256: fb4e305ae3a0fbbb7934e10d0b42436b156cf6ae3e83ab016009be05f31eda39
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting sites. The presence of multiple unknown reputation URLs suggests an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://decaiyun.com/upload/file/210903122240170749m5e0xx6j38ho.pdf In PDF document text
    • https://shoppingplanet.cityplanet.ro/ckfinder/userfiles/files/58363289859.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/vifafaj.pdfIn PDF document text
    • http://flightshop.jp/images/blog/file/72460265206.pdfIn PDF document text
    • https://sunriseinnjasper.com/nbloom/fckuploads/file/fodegobenagusubowigow.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/kebumegelaribijodofow.pdfIn PDF document text
    • http://comitatoamiantovelodromo.org/userfiles/file/90773528655.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/37371941492.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/ruxawuriwijekal.pdfIn PDF document text
    • https://ntiverification.com/userfiles/file/83703484800.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/98446710114.pdfIn PDF document text
    • http://citra.cl/userfiles/file/74398163463.pdfIn PDF document text
    • https://everestart.com/images/stories/file/bobitem.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/7829819586.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/28381615774.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210906181102.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/femipofin.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/84592391975.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613229a58db27---nebopovana.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/bakotugigovetaxuzilafeg.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613352e86b5ce---jaderozetigepabutugapewa.pdfIn PDF document text
    • http://shijijiaming.net/filespath/files/20210901224417.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/b81565ad1e6ad3819d4bdb254af5ffec/3722168391.pdfIn PDF document text
    • https://htijsr.com/userfiles/file/2351771896.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=rome+total+war+apk+installPDF 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_off0000b66a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB66A 16572 bytes
SHA-256: fb80abfd60ba0df90f1315684485d5a6cf0ec830d75ea1fd315d873e2f793682
font_01_sfnt_off0000e0d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D0 10636 bytes
SHA-256: 9fe906bd297f12202dd14fdbf263baa61de32834a91397058ea3081a548daa3e
font_02_sfnt_off0000f935.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF935 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1