Malicious PDF — malware analysis report

Static analysis result for SHA-256 71266f8f8fc4165a…

MALICIOUS

PDF

71.0 KB Created: 2021-10-01 12:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b36b24d507605c8a574a93144335ba68 SHA-1: 4c9542e24423b3a1074c9b4992baa7c44e1622ed SHA-256: 71266f8f8fc4165a5a733f1613bcd48385956189b26e0cd0289509ed6898bcda
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous external links, many hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to lead users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://smidgel.ru/uplcv?utm_term=locus+maps+apk PDF link annotation
    • http://nujhimachal.in/img/uploads/files/mupijekorudisapefa.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140bb7cdf62a---20925628576.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/dezufabotiv.pdfIn PDF document text
    • http://groupkaishan.com/d/files/76866394290.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161336d9333c8c---jokiwuzi.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/23137164424.pdfIn PDF document text
    • https://harmony-lazienka.pl/Upload/file/zoxivi.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155ff5c3e2ac---38189362863.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614ced6c4e94b---49551217729.pdfIn PDF document text
    • https://thisissati.com/userfiles/files/fisezikibekub.pdfIn PDF document text
    • https://renewone.de/files/jipuwarunejefu.pdfIn PDF document text
    • http://hbisan.com/userfiles/file/fojabozififubudopasoxuner.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/80350644492.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/posuva.pdfIn PDF document text
    • http://palami.by/images/file/jigib.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/ledetuxaxukide.pdfIn PDF document text
    • https://myshalewell.com/userfiles/file/perazopit.pdfIn PDF document text
    • http://arucax.am/user_images/file/purokevosuxisex.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/28/72367835750.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/lozudajasosazulerosadiji.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/54388638899.pdfIn PDF document text
    • http://bwlpsalisbury.com/uploads/files/rusegotude.pdfIn PDF document text
    • http://e1pl2.nazwa.pl/busy/fotki/file/xukutedezutawud.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_off0000b04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB04D 10112 bytes
SHA-256: c8b4ae7e4f56c63d3f1b103870feb0cd7975fa3b122f9fc3dd3045eaf41a8612
font_01_sfnt_off0000c6e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6E5 18544 bytes
SHA-256: eca7e2a1d528326b12f3e3de98d7e7b2c3d79f80d0aa6638d638fef7ebe96f1f
font_02_sfnt_off0000f6e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1