Malicious PDF — malware analysis report

Static analysis result for SHA-256 887e142d85d3d583…

MALICIOUS

PDF

75.8 KB Created: 2021-09-06 01:50:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ce8a59494269eb00cbe95977449405ea SHA-1: fd70458cafbb0b3073f8b1224962c6453db4a1c3 SHA-256: 887e142d85d3d58353d4393c87ee896fec12297587e94c6d2471bdcbfc2b52eb
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links pointing to compromised WordPress sites, specifically within form upload directories, indicating an attempt to host and distribute further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of embedded URLs and the nature of the heuristic firings point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://dothi.info/images/files/56466443876.pdf In PDF document text
    • https://tailormade-sales-marketing.com/userfiles/file/reboxoviwotarekoj.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16074d608ea261---1652254182.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f73f04cb48---raranitom.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/nli0mg9cu328ah4kv9gpch5rg2/ruwavojojisurusamara.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/43157905954.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/fuvovilipejekanufal.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/89297342455.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/c76c4b62e88ce7ff0611b34a3fde26dc/31434870534.pdfIn PDF document text
    • http://ccshecea.org/upload/files/riwubekurigujike.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/92707ce60f3fb5cb624bdae53a8e7ef9/5360970485.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/450cb646c2f1a2edfcfa4b24802ff636/tufesewo.pdfIn PDF document text
    • https://almudenafernandez.co/ckfinder/userfiles/Files/48701291860.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/72948498016.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/14869523961.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aef7f4bf92---24321797422.pdfIn PDF document text
    • http://agro-pasz.pl/ckfinder/userfiles/files/xopukimaxugodeziwesuj.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/9hi52qfv42vt9q1v66gasb55vn/jelakenizikubagezawiji.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/mimesiresad.pdfIn PDF document text
    • http://www.mmalappeenranta.com/tiedostot/files/bepituzenunuma.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086e3e71eb61---20307330128.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=pasos+para+cementar+una+incrustacion+de+ceromero+pdfPDF 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_off0000c011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC011 10836 bytes
SHA-256: 63a3f5135304744de352cf6b893312a2fd2f491c4438e2643a150751a2f68e3a
font_01_sfnt_off0000d920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD920 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f132.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF132 18964 bytes
SHA-256: 6a99f0f634e00d7ccdbfce9f18a48c1ca4dd88968e2a7dca334bdf104d223fc7