Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1a4d437f5cf15be…

MALICIOUS

PDF

86.9 KB Created: 2021-07-05 10:19:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 414d22b99279d6c8e857ad7ee2fc387f SHA-1: 0cdc1c4fadc94ff64d89a095366729e144c1ae26 SHA-256: d1a4d437f5cf15be3a151783569afd906545a9aa03e89b33eed4b984d5f5ec2e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with several heuristics indicating it functions as a link farm, including links to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites for phishing or further exploitation. No scripts were extracted, and the document body was unreadable, limiting the analysis of specific lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://kozelskadm.ru/files/uploads/files/disevazimawa.pdf In PDF document text
    • http://henanshuangxin.com/d/files/22818354759.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/guxijivigaluvaj.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/bulaxulesodosutemopemefu.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/27e97ae2b49b876c7cddb68b1e9e5e14/54704173989.pdfIn PDF document text
    • http://chickendaylacrescenta.com/uploads/files/46850446216.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8bc54458e---74165897033.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/zojegig.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a9d86ba24---61994961182.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/6796950371.pdfIn PDF document text
    • http://greenplanetnepal.com/userfiles/file/zanufevadukidibizi.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/2g3cb7i5rb3bcnu1eqssv8prsk/tefarexumipezarorefava.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/15b892c344564df2fa5341c7f259dfd0/44968188184.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb5c2399544---wojuzigusuvogegutitija.pdfIn PDF document text
    • http://orchid-daikanyama.com/userfiles/file/xuxazonanijabekumosomo.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/diwuvotan.pdfIn PDF document text
    • https://bbgpiti.com/userfiles/files/nuvibadapem.pdfIn PDF document text
    • https://valleyrestoration.net/home/apf/public_html/ckfinder/userfiles/files/vetuzezalobesifigu.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be5c7f385ec---guduxuvi.pdfIn PDF document text
    • http://apvn.info/userfiles/file/tanudosidopixuzumuwokofum.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd8dd57b5b---55348368687.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cf7887b9e---ranugaf.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160e070a6cd17d---tukowirewuralikixe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=stuart+wilde+the+trick+to+money+is+having+some+pdfPDF 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_off0000ea04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010216.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10216 18328 bytes
SHA-256: deb7794cd558b5ce1e558a1995a34886d92ef9b6c32e8f4776c70f8e721c756d
font_02_sfnt_off000132de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132DE 11600 bytes
SHA-256: f3a1c445b2a2349206531769887e58d1a7b7bd0cb19682bacdfaceb86f17650b