Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf9595ef4911b17e…

MALICIOUS

PDF

74.1 KB Created: 2021-09-02 00:28:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7fdd2a46191840be45af4bcef347f8ed SHA-1: d5841c76bd33f6be73e52fad376290c366e7f40c SHA-256: bf9595ef4911b17e2a5c73f7eb15900d49bb1610855dc402821b5afd12684c15
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous URLs, many of which are hosted on compromised CMS platforms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings clearly point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/f0ef9e9403fdb2492389e05b17db7bb3/25000544825.pdf In PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/161090da83c17d---zederawilomisowe.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/30323200088.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/60723048357.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/78457045885.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/65108405756.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859ef241476---xesuwipijatevikoza.pdfIn PDF document text
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/zekijetukutix.pdfIn PDF document text
    • http://churchontherockuk.org/home/churchontherock1/public_html/userfiles/files/mivefekep.pdfIn PDF document text
    • http://teleinwestor.com/userfiles/file/68645062890.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/8ffec8e21cc3c3c7a519f575aba86c80/mubanitabaduponabe.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/192237089193.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/zulejubinali.pdfIn PDF document text
    • https://groupburuemas2.com/contents//files/29468987468.pdfIn PDF document text
    • http://195exim.com/datas/files/73743116510.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a221dc992a4---xixolifotupisutep.pdfIn PDF document text
    • https://wipaphun.com/UserFiles/File/24870008494.pdfIn PDF document text
    • http://writtenmail.com/upload_images/file/6905606953.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084531fcd437---fokix.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/74644270351.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/ritunusatusog.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/c396bbe46c11a9beefba86ef54478356/robowejelisosobezeke.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce4763f219---25262120159.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/ridamipidibive.pdfIn PDF document text
    • http://ohsclassof73.com/clients/9/9a/9a21b0b253f7c4eafe662346d237c286/File/40808245382.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=am+is+are+was+were+exercisesPDF 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_off0000c1b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B8 10192 bytes
SHA-256: 3f30557b88883ee5fbfefbda5417913b0b67e3f23e24fdad0587b18334ab40c6
font_01_sfnt_off0000d89a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD89A 16228 bytes
SHA-256: a74a577374fa5cd3234401616bf100fa9fb1c732c28795372954ab8f34dbbb29
font_02_sfnt_off00010224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10224 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1