Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7dd7638fbc8cc4b…

MALICIOUS

PDF

83.6 KB Created: 2021-09-15 10:45:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c19fc87906c25ade9e570e10f1de2ee3 SHA-1: eab15cbf09a990cefa86fc4feccacae4a132755b SHA-256: a7dd7638fbc8cc4b199661a5d285b66a5f2289a6e4c020f8cf590c5a2dbca6f6
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3d8ded43a---rodujuzizutozelit.pdf In PDF document text
    • https://abyway.lv/images/ck_images/files/203018107.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/99119264669.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613146d1bc3ce---31266670993.pdfIn PDF document text
    • http://mclarenquartz.in/ci/userfiles/files/73440633766.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f0d4f81c9d---josopejapep.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021090645957_687356558.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/68948954037.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/jemamotezetovexoz.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/536562591.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/67814677040.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137a8fa32493---vilagibavegezigivulez.pdfIn PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/32254355580.pdfIn PDF document text
    • http://df-2.de/images/daten/file/tifowakujufus.pdfIn PDF document text
    • http://cy2hand.com/userfiles/bonoxixenopigom.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/juboxowapodudemovufer.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/pejawaverodoxulut.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613634a6a7fcf---pojatunaw.pdfIn PDF document text
    • http://konberdbio.com/upload/files/bilobumapuvaxunimefuta.pdfIn PDF document text
    • http://unseretochter.ch/images/file/85070991301.pdfIn PDF document text
    • https://thokhoavietnam.com/upload/files/6212052271.pdfIn PDF document text
    • http://debnine.net/UserFiles/File/33185708735.pdfIn PDF document text
    • http://sportsgarten.com/editorData/file/14655883888.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/5465870740.pdfIn PDF document text
    • http://naso10.com/userData/board/file/lekudibijixune.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/motodapufijerejaj.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/161414160719cf---77540976153.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=8+ball+pool+cheat+engine+long+linePDF 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_off0000dd01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f513.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF513 19268 bytes
SHA-256: b92297c3f4911043706aac5e3e40d21a8fe2bc60b47f4238fca7bc9ec16f2d84
font_02_sfnt_off0001288e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1288E 10636 bytes
SHA-256: c737d74a4d96704dd58a1088fa305a8289c16bb0459cfa54b0b3389846f2cdc5