Malicious PDF — malware analysis report

Static analysis result for SHA-256 f633bccdef3bfb36…

MALICIOUS

PDF

75.9 KB Created: 2021-09-05 11:07:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2103a1d5d9e5c0dcb92968fbcad6975a SHA-1: 4d7b5b8760d578c89be1e001dcb0e81c715e10dc SHA-256: f633bccdef3bfb36d7e9743869746955ca7796d1de1ff84e2cdaf71a8d4edc05
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lure users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://kystop.com/wp-content/plugins/super-forms/uploads/php/files/mkjlc1li2e5mp8u3a80thoarb5/80734669790.pdf
    • http://www.slenderclub.cz/ckfinder/userfiles/files/sutel.pdf
    • http://qigong.ru/userfiles/file/47964078263.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1609471e858feb---gedizepedonagonokat.pdf
    • https://badoza.net/userfiles/file/zobituka.pdf
    • http://chonburi33.com/userfiles/file/wabogumumutarexigovexe.pdf
    • http://bahtiyardishekimi.com/fckfiles/file/98073749853.pdf
    • http://sakaryakasaplarodasi.org/userfiles/file/12691154916.pdf
    • https://vendax.ro/files/file/40479243335.pdf
    • http://giaydantuongphongngudep.com/images/news/file/72259626511.pdf
    • https://cambodiaangkorhomestay.com/userfiles/file/kepalepuzilad.pdf
    • http://omg.su/upload/File/43018538383.pdf
    • http://blueyee.com/upload/file/05075748585.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/198f84de624975d9ec08784552b81a66/47094766729.pdf
    • http://brilspa.ro/userfiles/file///vixapumi.pdf
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/b5uhqmumvrmhooe7grpu76c8fe/35186954460.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160cd421f4a2cd---sigeroxezufijapumup.pdf
    • http://medicaldistri.com/ckfinder_files/files/tokuwenu.pdf
    • https://airshow-bg.com/file/13442948221.pdf
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/a1d7cd1fef98c56c13bc2ed92290d35f/pabeponogasupagevefiwew.pdf
    • https://debcopharma.com/userfiles/file/jazuzadejiruvinuwijuvi.pdf
    • https://kingwaterpure.com/ckfinder/userfiles/files/98665481984.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/n6liar5956gj3vm41ec4mvhq84/7040906670.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb802d3d81---49708320378.pdf
    • https://hirurgija.me//files/24488299348.pdf
    • http://haniltm.kr/upfiles/editor/files/40998812437.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=cara+potong+gambar+di+pdf
    • 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_off0000c6d9.bin
333dba1414b5c4f4ac667e4ebd4c83de454cc0fbf52a5f036a0180b4fe0b0c99
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6D9 16660 bytes
font_01_sfnt_off0000f231.bin
a7e22f311aa597c308881983cf287c8e2728d012dab0dcb8409daaf0d3c51fc8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF231 10664 bytes
font_02_sfnt_off00010a21.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A21 16792 bytes