Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bb13c99517fe395…

MALICIOUS

PDF

85.9 KB Created: 2021-09-13 02:45:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f345f33ca9117ca0abee27b1e648f017 SHA-1: 5f39c1fb74dcf1dfe3fafc34a206e9c0fbf71dbe SHA-256: 8bb13c99517fe3954319f1976036e32d6f4abcba0aac29c17d7ffeaa1f481ded
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one specifically identified as a lure for downloading software, and a heuristic indicating a fake invoice or payment lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to download a second-stage payload via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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=naruto+storm+4+for+android+free+download PDF link annotation
    • http://vkp.ru/upload/global/file/dorud.pdfIn PDF document text
    • http://52963566.com/upload/file/202109071645401617.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/79792753137.pdfIn PDF document text
    • https://arerp.kr/data/file///70345981482.pdfIn PDF document text
    • http://www.niceresidence.net/image/upload/File/94468232683.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/bekelefudet.pdfIn PDF document text
    • http://esen.life/userfiles/file/fupuwulax.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/58560634043.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///marosiwenobatikokuduborul.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/72218282735.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/rixifamaxomes.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///gotawazosamiwabiw.pdfIn PDF document text
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/vofapuxini.pdfIn PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/sesurojamumemawemoputiwod.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/lutowuzizuvuvisuvazasa.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lizabelorun.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/30244462452.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210907_8367025E3A926160.pdfIn PDF document text
    • https://movie2book.com/userfiles/file/xotajuxe.pdfIn PDF document text
    • http://progetec.org/userfiles/files/remomiwesiwiweguwos.pdfIn PDF document text
    • http://www.peretprod.ro/content-images/file/sebujovagawewubezebega.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/99274824437.pdfIn PDF document text
    • https://totalmediasolutions.ae/ckfinder/userfiles/files/16704861269.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/202191367518264.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/47311603263.pdfIn PDF document text
    • http://srtcivilnorth.com/ckeditor_file/files/kuwililuxawutuwisojo.pdfIn PDF document text
    • http://araonline.hu/uploads/file/13879585797.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/lusis.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_off0000ea36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA36 17872 bytes
SHA-256: 9658bbec456fdb1545745acdc4b8f1d7432c5dfb3bc80fd5b0ae1b55796c345e
font_01_sfnt_off00011884.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11884 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001309b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1309B 10756 bytes
SHA-256: 41bb3a65712b4c66ed4e4822034d2165190d76ecc315eced9682c611d34042b3