Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cdd57964a5135ea…

MALICIOUS

PDF

84.9 KB Created: 2021-09-03 11:51:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 7e72245c49569b67a491bd447980d2f6 SHA-1: a5d87a82eb559775c402c63bed85cdbc96fc6a69 SHA-256: 7cdd57964a5135ea64fc3eae9148b3de1663fc706b80496eb051ec683e046ab2
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://groupburuemas2.com/contents//files/mitut.pdf In PDF document text
    • http://mopron.ru/upload/files/58704226915.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e31e41b163---raxibuvotewufim.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070f71f5dc46---xitujowadabigi.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/xasajejobesanuseziriterev.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a24a22995d6---jaluzabizexefidewej.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160757cbc7dc7d---2617646538.pdfIn PDF document text
    • http://benevolo.it/userfiles/files/97258239517.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609223ea3f808---1965121109.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/861674d0563215e2612b95068c026d60/18056792856.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/pukiwolixiwalepavadodupif.pdfIn PDF document text
    • http://ukuleleceilidh.ca/clients/860383/File/godejanujokesuxufunarabuk.pdfIn PDF document text
    • https://fundreamz.com/ckfinder/userfiles/files/95601447202.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/48460090046.pdfIn PDF document text
    • http://stonebriarranch.com/clients/876969/File/73333615674.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/40138823723.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/88347491171.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eef2564870---50409422939.pdfIn PDF document text
    • http://miele-service-center.ru/uploads/files/74331160333.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16071702d7729d---jewofoxufafowuzofig.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16085a3adae67c---gipejawovibuwuvupexur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=introduction+to+business+finance+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_off0000e628.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE628 10756 bytes
SHA-256: 462e32d73f05a8a32efe9cec7e25e77d6fd702e5f7ada80755b065092fc19703
font_01_sfnt_off0000fed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED0 17544 bytes
SHA-256: 8b10e56f684303d80902bf715d03506237f307419bc1952c47020cafd4981271
font_02_sfnt_off00012c8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1