Malicious PDF — malware analysis report

Static analysis result for SHA-256 8da35d23a98286cc…

MALICIOUS

PDF

80.8 KB Created: 2021-09-14 08:31:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bfd808003cfd4fc1687e154969abf328 SHA-1: d7528d0ba347f523030eb1ef7b050b467c5d1ae2 SHA-256: 8da35d23a98286cc1514a645799b23e81abb1542a9e7522e1e01c67069aaed9f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://synerhu.ru/uplcv?utm_term=harga+hp+samsung+android+bekas PDF link annotation
    • https://santa.sg/images/users/00000000/files/27845125879.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/velewanunakamekadipowopez.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/41850751316.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/daxafebonatesifimabuxeniv.pdfIn PDF document text
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/42727884276.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/6aa676f05b020abc43a97af81b377aae/dibowafozubobegoxajadi.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/10292929985.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/78218221559.pdfIn PDF document text
    • http://dtyxbpzx.com/filespath/files/20210903134442.pdfIn PDF document text
    • https://mabuksusu2.com/contents/files/34855897978.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/norivojufetefesiro.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210911050909.pdfIn PDF document text
    • https://wedding-photos.cz/userfiles/file/99599694165.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/p13i3sn7vudbn5n3vrri0i1qg4/6555210316.pdfIn PDF document text
    • https://ms01bet.com/contents/files/damiritafaletesobanokudod.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613190b7243e5---49591440737.pdfIn PDF document text
    • http://transporteslaplata.com/imagenes_web/file/523803095.pdfIn PDF document text
    • http://cafemsoffice.com/userfiles/files/navotijemu.pdfIn PDF document text
    • https://media-get.com/userfiles/files/nisanuzomif.pdfIn PDF document text
    • http://reflita.lt/uploads/files/bamikixanofonal.pdfIn PDF document text
    • https://www.igescanada.com/ckfinder/userfiles/files/15068930968.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/161330442a0fd4---zibudejulamaz.pdfIn PDF document text
    • 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_off0000d8f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F9 11020 bytes
SHA-256: 62a8ee7f1daa747a3938b829bee0076e356994e5be0943f5a10ca384cb7e9d26
font_01_sfnt_off0000f1df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DF 16868 bytes
SHA-256: 0e11baea4ad2d812d63b6f2f99ee083252cf4ee4a160ab75f87b86f0088d75ad
font_02_sfnt_off00011dab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1