Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f11813c32581c47…

MALICIOUS

PDF

82.1 KB Created: 2021-09-05 08:26:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3337ff907b84fb29810f886366282b3f SHA-1: 50f2341cd7d84549e0569c38848145bf455ec481 SHA-256: 4f11813c32581c47a7964f064b04a5c4350eb75b6b104adcbb02fdafc1b47d0e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites and disposable hosting domains, which in turn host other PDF files. This suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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 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://lambanghieuquangcaogiare.net/vietkiendo/upload/file/46390643001.pdf In PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/o5uqhlkkmct5uq4rl9a03jgcgt/zozozeritamebe.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/67635194491.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/7667089241.pdfIn PDF document text
    • http://kleiberit.ru/files/file/6207811418.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/mofigoli.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de91e005083---35432835748.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16091988db62a2---narobatimidupebiwilitib.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082b3aea4857---forasopexole.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/ea20c301ec6faafba895f6ba110b9da3/28664834509.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088d4e5070ec---wakawajarorafeso.pdfIn PDF document text
    • http://pvvc.cz/files/puzupenonolulujavedibo.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076c2360d3b1---fororumilat.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/adaf3e9d18b64241497d310a6184d296/4291867993.pdfIn PDF document text
    • http://onellenorzes.com/uploads/files/27902614749.pdfIn PDF document text
    • https://szud94.hu/img/sajatfile/files/xilazasirizubofatulitanap.pdfIn PDF document text
    • http://alltechsro.cz/files/jatoperenaresumodul.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210522104113703.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607300c6e2a7f---kolavedove.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/xakiluradawifa.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/b5bef9c8d69274ebf518329ddff5eb65/69301468414.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/44150684641.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdf041421b2---rizekulumosiv.pdfIn PDF document text
    • http://uss100.com/clients/5/56/562308f4da1da23328cfd9e5c9f3e68f/File/49359664046.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=room+on+the+broom+book+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_off0000dae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F6 18700 bytes
SHA-256: dfe0860fb5d552ca18618af3d5f678c1a12be1656ad89098a0e275279fbae914
font_02_sfnt_off00012378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12378 10572 bytes
SHA-256: 9ced71f15056c7e970d3912b4dffcb547a1b93aec3a46a88d7a1321b18122057