Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27bb543775435a0…

MALICIOUS

PDF

81.6 KB Created: 2021-09-16 21:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: dd4686541bcfed7613a6384a1a6e2ce6 SHA-1: 3f4627249cf507b88637d5879fd7dc296b219293 SHA-256: a27bb543775435a0c9a7f72c838d043a65c2ca29cc09fce735216e015dafb6c1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, characteristic of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://vivo-mebel.ru/upload/file/bajevomezowojijugus.pdf In PDF document text
    • https://dawnraytech.985.tw/data/file/userfiles/files/muromepopone.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/19618962257.pdfIn PDF document text
    • http://abwalabamaave.com/uploads/files/niliwesikalokafujebuziv.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/58557848390.pdfIn PDF document text
    • http://www.examnotice.in/uploads/files/durelotoguluketisu.pdfIn PDF document text
    • http://medianet2000.net/amm_prod/image_news_popup/file/88404681980.pdfIn PDF document text
    • http://chromavials.com/d/files/33143413208.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210916_145024.pdfIn PDF document text
    • https://nakipoglugroup.com/upload/ckfinder/files/1935081995.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/161384f7170ce3---mudizamime.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/gilerunifasagowet.pdfIn PDF document text
    • http://maksimetall.ru/files/41477976817.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/16869586704.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/47029730445.pdfIn PDF document text
    • http://icltindia.in/userfiles/file/24540707388.pdfIn PDF document text
    • https://alebusph.centralcms.cloud/galeria/files/43612637336.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136586325188---88426012760.pdfIn PDF document text
    • http://brenderup.ro/mm/file/71110621107.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/jovadolomuxawedilitavezeb.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dc66618117---getudezibemulu.pdfIn PDF document text
    • http://daming-school.com/userfiles/file/11551550602.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/j8go58vv73tarsf004igjovvm5/tutivemokawiwewexu.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/dujukuzidojowobi.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/sapubuvomibokawura.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=club+android+mobilePDF 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_off0000da7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA7F 10416 bytes
SHA-256: 3f88b6aa30a44c3a2b55131acf5ff043b772a91cade66499ce51a124c31c3f01
font_01_sfnt_off0000f1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0B 17928 bytes
SHA-256: 86f5c5e21369b4b78f52b1fe0ba768acff761bfed634eece1206ef8aaf42c2fb