Malicious PDF — malware analysis report

Static analysis result for SHA-256 3859609d7153d526…

MALICIOUS

PDF

85.4 KB Created: 2021-09-06 00:02:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bfbd9584ad0dfd68dfa66998cbc2202d SHA-1: 1e52683264d430967217419638655bbfa0e0f7af SHA-256: 3859609d7153d5262b312ec814ec729727b276d99fd369a817eaed046cab99eb
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicates maliciousness, and the structure aligns with techniques used to distribute further malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 5

  • 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://laborke.ru/uplcv?utm_term=grounded+theory+approach+pdf PDF link annotation
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609062e25eae7---94853175474.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8ff4b623a---wirojepokixuzosunemanev.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/telasuju.pdfIn PDF document text
    • http://mwcapital.net//ckfinder/userfiles/files/sogiburifekowo.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/5ab9e107c3890fb23d7ec44dacde4844/45048929659.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/79870200057.pdfIn PDF document text
    • https://www.borzabadi.com/ckfinder/userfiles/files/funol.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/34888553715.pdfIn PDF document text
    • https://arerp.kr/data/file///17575058182.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/28454249191.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/dedifopifidelaramat.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/kuce7gell57ipq03mioc4prhei/wuberadajiwubupukob.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/abbd58eab64958b7619ee8eed2517f95/niperuxusifal.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/70259194443.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/bemakazizi.pdfIn PDF document text
    • https://bawaniint.com/ckfinder/userfiles/files/ziperadalazenovuzagif.pdfIn PDF document text
    • https://farmacieitaliane.com/documenti/file/dadujewujunubakimi.pdfIn PDF document text
    • http://golden-candies.ru/webroot/files/files/79416149053.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/29058551912.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca2ea39b3c---55349962977.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f98ec63b9---9277572562.pdfIn PDF document text
    • http://geotersrl.it/file/pifamikikakotime.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/78db1b740057a9fa461f2633865fdb56/raxofezaxisowenudikur.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/28114256716.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/zipifowipavekakoxabineso.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c37120c7b8f---82009214615.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5548cd066---gokulaxuforodatuvuf.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_off0000e8f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001010b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1010B 18016 bytes
SHA-256: 65b7494afaf874c3c3417947b871e48252b4e93ec2bed471403666f6ece42659
font_02_sfnt_off00012fbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FBD 10664 bytes
SHA-256: ee59b58c9a7f1ea080a139a6cbe35b0a5ed909c2eecde87e1b90f8f38f141986