Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c97de82814d66ca…

MALICIOUS

PDF

74.5 KB Created: 2021-09-22 19:03:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d3c9800099983fb1e108bc35db0c6f52 SHA-1: 42d0c8a92441170bca92b13eb3f3241a434c7232 SHA-256: 4c97de82814d66cac31ce4f02ab5b7a085342a2f6dc52eef7f1752b5f41ba442
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of link farms hosted on compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=123movies+this+is+us+season+4 PDF link annotation
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/jewaxewadupewajalokox.pdfIn PDF document text
    • https://icbacademy.com/upload/files/mokibukanef.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/83320446616.pdfIn PDF document text
    • https://budgetparking.ca/admin/uploads/file/taliruduxejukug.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-9-19/20210919145832613642.pdfIn PDF document text
    • https://beeshark.ro/app/webroot/files/userfiles/files/kidokupuwonegefitopikipet.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/65313129677.pdfIn PDF document text
    • http://muabannhagiare.net/images/uploads/files/12026489589.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/goriweweziburezoxesideki.pdfIn PDF document text
    • http://xhslsh.gdx.cn/ckfinder/userfiles/files/sewalegexowakes.pdfIn PDF document text
    • https://triosms.com/userfiles/file/51193780179.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/9867376053.pdfIn PDF document text
    • http://pegastelco.com/pictures/files/sabazafazorisimutafaxoxe.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/vilazopinurigiwoxi.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/48853923968.pdfIn PDF document text
    • http://artio.pl/files/files/72386900282.pdfIn PDF document text
    • http://jingyitech.com/uploadfile/42143873572.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/78183217897.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a95a6d31de---80027717237.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021090216362287.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130fc7216cae---9438770908.pdfIn PDF document text
    • https://poulinstrapscan.com/userfiles/file/dixiduzasogaderitudalape.pdfIn PDF document text
    • http://softwaretesting.kr/club/data/userfiles/file/20210908184323.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/161378fc0da537---82870686504.pdfIn PDF document text
    • https://repetitorebi.ge/userfiles/files/gogozoxuvel.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_off0000c121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC121 10716 bytes
SHA-256: 48be0ff1114551ca9df6e685917f72113d3e3c8571c268a00c16c17fa618c6de
font_01_sfnt_off0000d9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B5 16968 bytes
SHA-256: 4328944b5074eede6e95b7967fa53d91c3d038682586c832aa714847f3422b74
font_02_sfnt_off000104d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1