Malicious PDF — malware analysis report

Static analysis result for SHA-256 e983542f8503c571…

MALICIOUS

PDF

84.9 KB Created: 2021-09-15 19:32:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 45bef4b6535f1d8ea459aeeb4afed863 SHA-1: b523a311d35730ee869b59f697b4330b8d547d69 SHA-256: e983542f8503c571e0fa08359a1c9406b9ea68d39372178f402efb31f1e61506
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' specifically highlights a link to a compromised WordPress upload storage, further supporting the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://congthuonghotel.vn/app/webroot/files/images/pages/files/75310418920.pdf In PDF document text
    • https://yellowstonewildlife.com/vekatolewatukawuroja.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021091413482573499.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/29583881167.pdfIn PDF document text
    • https://handientu.vn/userfiles/file/11570057146.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbd78532c3---wemakamepewojuf.pdfIn PDF document text
    • http://winterwonderlandzundert.nl/uploadimages/files/sepizoji.pdfIn PDF document text
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/20929578712.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/15250501983.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/ee9825ead47a231fe15f092d3a49b13d/77553390412.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/zexinaviwexogiposowuku.pdfIn PDF document text
    • http://brno-skoleniridicu.cz/ckfinder/userfiles/files/vexanugogofesuwux.pdfIn PDF document text
    • http://3colorjazz.com/fckeditor/userfiles/image/rorujolat.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/juxusegetekefo.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/kokepasafanejugase.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/pariwubuzugavuse.pdfIn PDF document text
    • http://jncs.kr/page_data/file/20210909182743.pdfIn PDF document text
    • https://kluchar.net/klucharnet/images/file/zizivudowepuzidage.pdfIn PDF document text
    • http://kidsjeodo.com/images/files/21146008206.pdfIn PDF document text
    • http://master-br.ru/img/file/42507397770.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d37bcc16a---jajolojoworunajetebu.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/27890638043.pdfIn PDF document text
    • https://lifesmart.lifesmart.ro/ckfinder/userfiles/files/rilexuduxoliwasal.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/77221107700.pdfIn PDF document text
    • http://eqletstalk.com/uploads/files/202109131710425906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=streaming+sports+free+sitesPDF 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_off0000e76e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76E 17648 bytes
SHA-256: 0f11ada0f2e1fe2cb01f6007c816f06b45929c75e77bb93d0a89a7c5127a112d
font_01_sfnt_off0001151e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1151E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D35 10728 bytes
SHA-256: 53b7cc8bfc83c8f27ac65cfd446e3dd122f7a629b5c7cca94e133c53607e5f4c