Malicious PDF — malware analysis report

Static analysis result for SHA-256 91990f21271053cc…

MALICIOUS

PDF

68.5 KB Created: 2021-09-13 05:19:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bcc99ef4e3eceb9d5fe348ae70a2a9cb SHA-1: 8652aed6cbbdf3669860f6e811f37bc200d9d39f SHA-256: 91990f21271053cc53bd7d65262731bab77eccc67a81f8ab4653356de3e2ef1c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to various websites, many of which appear to be compromised CMS uploads or hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/efp19f56cm1lblkecvd2n4h47u/78064869341.pdf In PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/50327813341.pdfIn PDF document text
    • http://brunagabriele.it/userfiles/files/robamebokabirexoxilogufe.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/ledadiviridoxitodekami.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/temikamo.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/97022156889.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea764ed45e---32350217948.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/literunagezu.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210908_DD7DB857C2DE3A66.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/48765259002.pdfIn PDF document text
    • https://tjp2-hotlink-j3t.com/contents/files/72499671208.pdfIn PDF document text
    • http://thaiboxes.com/piceditor/file/kumomuz.pdfIn PDF document text
    • http://herborgthailand.com/file_media/file_image/file/xutebikomevuluto.pdfIn PDF document text
    • https://red-adlay.com/upload/files/77976418738.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/34537625966.pdfIn PDF document text
    • https://snowcat.pl/admin/ckfinder/userfiles/files/xakavufumor.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/gowudoju.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/pawifimak.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bc370493a809785df97839c5487366e8/gesisuwiwor.pdfIn PDF document text
    • https://digireg.si/upload/36047626973.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/damadabejuve.pdfIn PDF document text
    • https://motoquadro.de/userfiles/file/55870436716.pdfIn PDF document text
    • http://antitumor.org/filespath/files/20210910111731.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/34057603334.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/47790205154.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=disney+character+flikPDF 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_off0000b0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CE 14440 bytes
SHA-256: 48a3d77747fa9f299b6bd6f4fff74a4908ae782ae998c939999968789454bf23
font_01_sfnt_off0000d49f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ecb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB6 10520 bytes
SHA-256: ac082c817fe7514b917c322ad359953188e61bd648d8861c67d6322ac3f32bf8

Open this report in the interactive analyzer, or submit your own file for analysis.