Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56723e165b20e35…

MALICIOUS

PDF

93.9 KB Created: 2021-07-12 22:55:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 07a8964afcc7ad3d906255b66718f257 SHA-1: edc10755490ad5827bdcb40efebcc259b6478edf SHA-256: a56723e165b20e358d9114e77ec0ebe0c4e0e750d0d72ec51ede0a04fc6b7241
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised CMS uploads, suggesting it functions as a link farm to distribute malicious content or phish for information. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the document is designed to host a large number of links on potentially disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://philabc.ru/uplcv?utm_term=do+you+need+a+smear+after+hysterectomy PDF link annotation
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160962743bda4a---nagedoruxibifupobinuriza.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/8108353593.pdfIn PDF document text
    • https://emmaushuis.org/pages/xirulobosigutorazuzavoxe.pdfIn PDF document text
    • http://savages.lu/imagesRTE/files/wanav.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/demapezekiriketabuzapab.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16094877b57055---kuvixipikogiludojaripoga.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/venaxogalopa.pdfIn PDF document text
    • http://studioarchperissinotto.eu/userfiles/files/11215875362.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/37obs7t359kt5smcnt5jk21vc5/gipedakavira.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7a12bd5eb---72172641164.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb5069a8729---didaram.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6875f2c1a---61961923136.pdfIn PDF document text
    • https://ilcaminodaugo.it/file/8576151688.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/jitukudiwonamamalem.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607652d8b1d7d---4372063968.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/sifoginajemunonamidavogev.pdfIn PDF document text
    • https://pergamine.com/ckfinder/userfiles/files/53879186453.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8b56884ee---28292975122.pdfIn PDF document text
    • http://sammyuriasproperties.com/userfiles/files/norulafixamom.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c851082ea4b---tumuf.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/81507611229.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079c1db6e21a---71299620391.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_off00010d78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001258a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1258A 16976 bytes
SHA-256: 1088e45ea81cfc77b970caf23a1bd972c681421806a05b43f3dbadb462361f71
font_02_sfnt_off000151c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151C4 10816 bytes
SHA-256: c0baf7a05614bf92fada9c43bcb2217596eb61c538eafabef21bf588f67df2c0