Malicious PDF — malware analysis report

Static analysis result for SHA-256 52a9897e61b608df…

MALICIOUS

PDF

87.1 KB Created: 2021-09-14 13:57:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b0114d5bc29e1881a3f1c81f120fd01b SHA-1: 8b51251b49c4970ddd6f45eee3684c5b963596a0 SHA-256: 52a9897e61b608df748368788b9cc109eb423d91d4b7bc507482e5a30dbe75ae
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress sites or disposable hosting, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of common phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zkmeiqi.com/admin/ckfinder/upfile/files/86146824697.pdf In PDF document text
    • https://12shio2.com/contents/files/12906339668.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/kajitopusakexabux.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/8870355185.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/lexilepitaji.pdfIn PDF document text
    • https://4of100churchstreet.com/assets/media/files/gewidojukabusazorurufex.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa9f9c176f---xufolas.pdfIn PDF document text
    • http://boothbayharborshipyard.com/userfiles/file/19872600662.pdfIn PDF document text
    • http://phongkhamthienhoa.vn/images/files/57542128938.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/bigegemanufovi.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/rotuxekesijovamafu.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/3sl2pm9kao7ino1jjblvsq04g1/sofinanakiroze.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/98212587585.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210907_170213.pdfIn PDF document text
    • https://benmoonpharma.com/userfiles/file/64708648408.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021090304171473499.pdfIn PDF document text
    • http://resurrection-life.net/userfiles/files/30440127086.pdfIn PDF document text
    • https://sintasyapi.com/img/userfiles/file/9618703306.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/zokasobubezab.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f6cc6a4e83---xutesomuse.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/15577208656.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/wotivemewazugome.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/zuwukizi.pdfIn PDF document text
    • http://nato-denkmal.de/uploads/file/vewudafefoveto.pdfIn PDF document text
    • http://sungder.com/upload/kaxadu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=add+fingerprint+androidPDF 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_off0000ef97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF97 18256 bytes
SHA-256: 6d160fecb71c3c5f3603e91c95d43ac865fbf5d249956bfe486d64fbbf53b445
font_01_sfnt_off00011ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001370d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1370D 10440 bytes
SHA-256: 290815bdbe1edd811ea3eaf8e1898363410f57d2fc42acfa87cc358d507a2125