Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa89a409871e97a3…

MALICIOUS

PDF

74.0 KB Created: 2021-09-21 08:53:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d9a8a194383ca191f2071b2f49e856ba SHA-1: b163532ff097e3548252160113285590d5b22909 SHA-256: aa89a409871e97a3ec942b5b0ea58ac35b39251aaf410b3d2c5da49d748e7647
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics and ClamAV as malicious, specifically indicating phishing and trojan activity. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • 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.
  • 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://allytemp.ru/uplcv?utm_term=hacker%27s+keyboard+gta+vice+city PDF link annotation
    • http://sinoscaform.com/upload/ckimg/files/202109201544268827.pdfIn PDF document text
    • http://ticaproduce.com/ckfinder/userfiles/files/wopaforoburovakexo.pdfIn PDF document text
    • http://fkhd.cz/data/img/64504621599.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/vesolasexufupewilobimaw.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161478603eb712---20247654009.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/domapepevapo.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/37eac29e520cbc55d88ce28feec6fccf/99549069500.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/7893c2c07bbe917bc6adfa85aa40bf6c/41870364443.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/pebupositabixejaxapopepi.pdfIn PDF document text
    • http://insuralead.com/userfiles/file/medavedonupasuxesawuguz.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/wisufixozewan.pdfIn PDF document text
    • https://marikakozmetika.hu/editor_up/gowezapar.pdfIn PDF document text
    • http://abwingsmd.com/uploads/files/46315448778.pdfIn PDF document text
    • https://yuvasarkar.org/userfiles/file/daluzikokuboxazedosano.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090119590663.pdfIn PDF document text
    • https://tedvandergulik.nl/userimages/file/kirefakasumajegagusam.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/galemebaxanidimatusom.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///desoxikategemo.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161362bd86531b---resoxolegeg.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/87362341476.pdfIn PDF document text
    • http://sayarbobinaj.com/file/xifuwibilapuzejaj.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/161323ae5a5df0---80746003386.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/kagufelisamesefusadadiv.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16146fc1e09581---86708421758.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/zopuzulekenoruzozazosepot.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/41277536460.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_off0000bbe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBE7 10832 bytes
SHA-256: 5164c30f926fb4b2fb161a89951063be001b8021723bcf9515282c09980f2c26
font_01_sfnt_off0000d4ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4EA 17428 bytes
SHA-256: e82565494250981cc9d16a017719e52ca9027c9ebd5a212620a4b41bbc11dc24
font_02_sfnt_off00010208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10208 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1