Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fa24380399e6524…

MALICIOUS

PDF

83.6 KB Created: 2021-09-19 16:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d6a07330f810ab4d48d54e3d5309994 SHA-1: 6ab94745597a0289fbe65336a1bb150762e642e5 SHA-256: 3fa24380399e6524a93614b11370ade13e9e2a3ec91c2e17a22ff215e5620bcc
176 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous websites, many of which are hosted on disposable domains or compromised CMS instances. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://mclarenquartz.in/ci/userfiles/files/72579367409.pdf
    • http://thongthien.vn/upload/files/namokodijuwulid.pdf
    • http://dison.cn/filespath/files/20210910032457.pdf
    • https://lacgl.org/upload/editor/file/79740399187.pdf
    • http://studiomarazzi.eu/userfiles/files/45673395446.pdf
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/20028114857.pdf
    • https://tectrongim.com/uploads/file/lusaze.pdf
    • http://tsyrulnikov.ru/upload/file/59491606568.pdf
    • http://pluimveebeurs.com/userfiles/file/13652491405.pdf
    • https://alusol-kw.com/ckfinder/userfiles/files/11994662274.pdf
    • http://ccsctda.com/ckfinder/userfiles/files/20210904_120243.pdf
    • https://groupunsur1.com/contents/files/75260127066.pdf
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5e969325b---mafavezebiner.pdf
    • http://jmk.kr/ckfinder/userfiles/files/zebogisik.pdf
    • http://giovanniseneca.eu/userfiles/files/57276869078.pdf
    • https://indianhairtransplant.com/ckfinder/userfiles/files/jusagusosimasimalobaves.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614735adc249b---25256691191.pdf
    • http://w-f-l.de/user_img/file/fowajapikunalawugaxazozur.pdf
    • http://rothemtour.com/FileData/ckfinder/files/20210908_EE51CC96F1826CE9.pdf
    • http://deurenhanger.nl/userfiles/file/sibiwikimutazese.pdf
    • http://hyundai-dongdo.vn/images/files/fumiridalijif.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/304bc605f7683e77973dedba510face6/94297830553.pdf
    • https://groupburuemas1.com/contents/files/jovesefakilugus.pdf
    • http://sumtinathholidays.com/admin/uploadfiles/file/rebulaxiz.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144ac4f1fee7---rumamovomuvupuzivubono.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=apk+fortnite+play+store
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e166.bin
8c8213b6db9ec1e81a60e6ea27d432a35eb18b864f8bb5b3092568d1be69c779
pdf-font-stream PDF embedded font (sfnt) at offset 0xE166 10540 bytes
font_01_sfnt_off0000f99d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF99D 16792 bytes
font_02_sfnt_off000111af.bin
17dfe7de2e546592c8e5d578e82db094599a2b784127d7ed3380abb5b325278d
pdf-font-stream PDF embedded font (sfnt) at offset 0x111AF 18324 bytes